first commit

plugins/system/accessibility/accessibility.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_accessibility</name>
+	<author>Joomla! Project</author>
+	<creationDate>2020-02-15</creationDate>
+	<copyright>(C) 2020 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.0.0</version>
+	<description>PLG_SYSTEM_ACCESSIBILITY_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Accessibility</namespace>
+	<files>
+		<folder plugin="accessibility">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages folder="admin">
+		<language tag="en-GB">language/en-GB/plg_system_accessibility.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_accessibility.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="section"
+					type="list"
+					label="PLG_SYSTEM_ACCESSIBILITY_SECTION"
+					default="administrator"
+					validate="options"
+					>
+					<option value="site">PLG_SYSTEM_ACCESSIBILITY_SECTION_SITE</option>
+					<option value="administrator">PLG_SYSTEM_ACCESSIBILITY_SECTION_ADMIN</option>
+					<option value="both">PLG_SYSTEM_ACCESSIBILITY_SECTION_BOTH</option>
+				</field>
+				<field
+					name="useEmojis"
+					type="list"
+					label="PLG_SYSTEM_ACCESSIBILITY_EMOJIS"
+					default="true"
+					validate="options"
+					>
+					<option value="true">PLG_SYSTEM_ACCESSIBILITY_EMOJIS_TRUE</option>
+					<option value="false">PLG_SYSTEM_ACCESSIBILITY_EMOJIS_FALSE</option>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/accessibility/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.accessibility
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Accessibility\Extension\Accessibility;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Accessibility(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'accessibility')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/accessibility/src/Extension/Accessibility.php

@@ -0,0 +1,114 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.accessibility
+ *
+ * @copyright   (C) 2020 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Accessibility\Extension;
+
+use Joomla\CMS\Plugin\CMSPlugin;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * System plugin to add additional accessibility features to the administrator interface.
+ *
+ * @since  4.0.0
+ */
+final class Accessibility extends CMSPlugin
+{
+    /**
+     * Add the javascript for the accessibility menu
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onBeforeCompileHead()
+    {
+        $section = $this->params->get('section', 'administrator');
+
+        if ($section !== 'both' && $this->getApplication()->isClient($section) !== true) {
+            return;
+        }
+
+        // Get the document object.
+        $document = $this->getApplication()->getDocument();
+
+        if ($document->getType() !== 'html') {
+            return;
+        }
+
+        // Are we in a modal?
+        if ($this->getApplication()->getInput()->get('tmpl', '', 'cmd') === 'component') {
+            return;
+        }
+
+        // Load language file.
+        $this->loadLanguage();
+
+        // Determine if it is an LTR or RTL language
+        $direction = $this->getApplication()->getLanguage()->isRtl() ? 'right' : 'left';
+
+        // Detect the current active language
+        $lang = $this->getApplication()->getLanguage()->getTag();
+
+        /**
+        * Add strings for translations in Javascript.
+        * Reference  https://ranbuch.github.io/accessibility/
+        */
+        $document->addScriptOptions(
+            'accessibility-options',
+            [
+                'labels' => [
+                    'menuTitle'           => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_MENU_TITLE'),
+                    'increaseText'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_INCREASE_TEXT'),
+                    'decreaseText'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_DECREASE_TEXT'),
+                    'increaseTextSpacing' => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_INCREASE_SPACING'),
+                    'decreaseTextSpacing' => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_DECREASE_SPACING'),
+                    'invertColors'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_INVERT_COLORS'),
+                    'grayHues'            => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_GREY'),
+                    'underlineLinks'      => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_UNDERLINE'),
+                    'bigCursor'           => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_CURSOR'),
+                    'readingGuide'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_READING'),
+                    'textToSpeech'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_TTS'),
+                    'speechToText'        => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_STT'),
+                    'resetTitle'          => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_RESET'),
+                    'closeTitle'          => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_ACCESSIBILITY_CLOSE'),
+                ],
+                'icon' => [
+                    'position' => [
+                        $direction => [
+                            'size'  => '0',
+                            'units' => 'px',
+                        ],
+                    ],
+                    'useEmojis' => $this->params->get('useEmojis', 'true') === 'true',
+                ],
+                'hotkeys' => [
+                    'enabled'    => true,
+                    'helpTitles' => true,
+                ],
+                'textToSpeechLang' => [$lang],
+                'speechToTextLang' => [$lang],
+            ]
+        );
+
+        $document->getWebAssetManager()
+            ->useScript('accessibility')
+            ->addInlineScript(
+                'window.addEventListener("load", function() {'
+                . 'new Accessibility(Joomla.getOptions("accessibility-options") || {});'
+                . '});',
+                ['name' => 'inline.plg.system.accessibility'],
+                ['type' => 'module'],
+                ['accessibility']
+            );
+    }
+}

plugins/system/actionlogs/actionlogs.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_actionlogs</name>
+	<author>Joomla! Project</author>
+	<creationDate>2018-05</creationDate>
+	<copyright>(C) 2018 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.9.0</version>
+	<description>PLG_SYSTEM_ACTIONLOGS_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\ActionLogs</namespace>
+	<files>
+		<folder>forms</folder>
+		<folder plugin="actionlogs">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_actionlogs.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_actionlogs.sys.ini</language>
+	</languages>
+</extension>

plugins/system/actionlogs/forms/actionlogs.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fieldset name="actionlogs" label="PLG_SYSTEM_ACTIONLOGS_OPTIONS" addfieldprefix="Joomla\Component\Actionlogs\Administrator\Field">
+		<fields name="actionlogs">
+			<field
+				name="actionlogsNotify"
+				type="radio"
+				label="PLG_SYSTEM_ACTIONLOGS_NOTIFICATIONS"
+				layout="joomla.form.field.radio.switcher"
+				default="0"
+				filter="integer"
+				required="true"
+				>
+				<option value="0">JNO</option>
+				<option value="1">JYES</option>
+			</field>
+			<field
+				name="actionlogsExtensions"
+				type="logtype"
+				label="PLG_SYSTEM_ACTIONLOGS_EXTENSIONS_NOTIFICATIONS"
+				multiple="true"
+				validate="options"
+				layout="joomla.form.field.list-fancy-select"
+				showon="actionlogsNotify:1"
+				default="com_content"
+			/>
+		</fields>
+	</fieldset>
+</form>

plugins/system/actionlogs/forms/information.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fields name="params">
+		<fieldset name="information" label="PLG_SYSTEM_ACTIONLOGS_OPTIONS">
+			<field addfieldprefix="Joomla\Component\Actionlogs\Administrator\Field"
+				name="Information"
+				type="plugininfo"
+				label="PLG_SYSTEM_ACTIONLOGS_INFO_LABEL"
+				description="PLG_SYSTEM_ACTIONLOGS_INFO_DESC"
+			/>
+		</fieldset>
+	</fields>
+</form>

plugins/system/actionlogs/services/provider.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.actionlogs
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserFactoryInterface;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\ActionLogs\Extension\ActionLogs;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin = new ActionLogs(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'actionlogs')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+                $plugin->setUserFactory($container->get(UserFactoryInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/actionlogs/src/Extension/ActionLogs.php

@@ -0,0 +1,350 @@
+<?php
+
+/**
+ * @package     Joomla.Plugins
+ * @subpackage  System.actionlogs
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\ActionLogs\Extension;
+
+use Joomla\CMS\Form\Form;
+use Joomla\CMS\HTML\HTMLHelper;
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserFactoryAwareTrait;
+use Joomla\Component\Actionlogs\Administrator\Helper\ActionlogsHelper;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Database\Exception\ExecutionFailureException;
+use Joomla\Database\ParameterType;
+use Joomla\Event\DispatcherInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! Users Actions Logging Plugin.
+ *
+ * @since  3.9.0
+ */
+final class ActionLogs extends CMSPlugin
+{
+    use DatabaseAwareTrait;
+    use UserFactoryAwareTrait;
+
+    /**
+     * Constructor.
+     *
+     * @param   DispatcherInterface  $dispatcher   The dispatcher
+     * @param   array                $config       An optional associative array of configuration settings
+     *
+     * @since   3.9.0
+     */
+    public function __construct(DispatcherInterface $dispatcher, array $config)
+    {
+        parent::__construct($dispatcher, $config);
+
+        // Import actionlog plugin group so that these plugins will be triggered for events
+        PluginHelper::importPlugin('actionlog');
+    }
+
+    /**
+     * Adds additional fields to the user editing form for logs e-mail notifications
+     *
+     * @param   Form   $form  The form to be altered.
+     * @param   mixed  $data  The associated data for the form.
+     *
+     * @return  boolean
+     *
+     * @since   3.9.0
+     *
+     * @throws  \Exception
+     */
+    public function onContentPrepareForm(Form $form, $data)
+    {
+        $formName = $form->getName();
+
+        $allowedFormNames = [
+            'com_users.profile',
+            'com_users.user',
+        ];
+
+        if (!\in_array($formName, $allowedFormNames, true)) {
+            return true;
+        }
+
+        /**
+         * We only allow users who have Super User permission to change this setting for themselves or for other
+         * users who have the same Super User permission
+         */
+        $user = $this->getApplication()->getIdentity();
+
+        if (!$user || !$user->authorise('core.admin')) {
+            return true;
+        }
+
+        // Load plugin language files.
+        $this->loadLanguage();
+
+        // If we are on the save command, no data is passed to $data variable, we need to get it directly from request
+        $jformData = $this->getApplication()->getInput()->get('jform', [], 'array');
+
+        if ($jformData && !$data) {
+            $data = $jformData;
+        }
+
+        if (\is_array($data)) {
+            $data = (object) $data;
+        }
+
+        if (empty($data->id) || !$this->getUserFactory()->loadUserById($data->id)->authorise('core.admin')) {
+            return true;
+        }
+
+        Form::addFormPath(JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name . '/forms');
+
+        if ((!PluginHelper::isEnabled('actionlog', 'joomla')) && ($this->getApplication()->isClient('administrator'))) {
+            $form->loadFile('information', false);
+
+            return true;
+        }
+
+        if (!PluginHelper::isEnabled('actionlog', 'joomla')) {
+            return true;
+        }
+
+        $form->loadFile('actionlogs', false);
+
+        return true;
+    }
+
+    /**
+     * Runs on content preparation
+     *
+     * @param   string  $context  The context for the data
+     * @param   object  $data     An object containing the data for the form.
+     *
+     * @return  boolean
+     *
+     * @since   3.9.0
+     */
+    public function onContentPrepareData($context, $data)
+    {
+        if (!\in_array($context, ['com_users.profile', 'com_users.user'])) {
+            return true;
+        }
+
+        if (\is_array($data)) {
+            $data = (object) $data;
+        }
+
+        if (empty($data->id) || !$this->getUserFactory()->loadUserById($data->id)->authorise('core.admin')) {
+            return true;
+        }
+
+        $db = $this->getDatabase();
+        $id = (int) $data->id;
+
+        $query = $db->getQuery(true)
+            ->select($db->quoteName(['notify', 'extensions']))
+            ->from($db->quoteName('#__action_logs_users'))
+            ->where($db->quoteName('user_id') . ' = :userid')
+            ->bind(':userid', $id, ParameterType::INTEGER);
+
+        try {
+            $values = $db->setQuery($query)->loadObject();
+        } catch (ExecutionFailureException $e) {
+            return false;
+        }
+
+        if (!$values) {
+            return true;
+        }
+
+        // Load plugin language files.
+        $this->loadLanguage();
+
+        $data->actionlogs                       = new \stdClass();
+        $data->actionlogs->actionlogsNotify     = $values->notify;
+        $data->actionlogs->actionlogsExtensions = $values->extensions;
+
+        if (!HTMLHelper::isRegistered('users.actionlogsNotify')) {
+            HTMLHelper::register('users.actionlogsNotify', [__CLASS__, 'renderActionlogsNotify']);
+        }
+
+        if (!HTMLHelper::isRegistered('users.actionlogsExtensions')) {
+            HTMLHelper::register('users.actionlogsExtensions', [__CLASS__, 'renderActionlogsExtensions']);
+        }
+
+        return true;
+    }
+
+    /**
+     * Utility method to act on a user after it has been saved.
+     *
+     * @param   array    $user     Holds the new user data.
+     * @param   boolean  $isNew    True if a new user is stored.
+     * @param   boolean  $success  True if user was successfully stored in the database.
+     * @param   string   $msg      Message.
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onUserAfterSave($user, $isNew, $success, $msg): void
+    {
+        if (!$success) {
+            return;
+        }
+
+        // Clear access rights in case user groups were changed.
+        $userObject = $this->getUserFactory()->loadUserById($user['id']);
+        $userObject->clearAccessRights();
+
+        $authorised = $userObject->authorise('core.admin');
+        $userid     = (int) $user['id'];
+        $db         = $this->getDatabase();
+
+        $query = $db->getQuery(true)
+            ->select('COUNT(*)')
+            ->from($db->quoteName('#__action_logs_users'))
+            ->where($db->quoteName('user_id') . ' = :userid')
+            ->bind(':userid', $userid, ParameterType::INTEGER);
+
+        try {
+            $exists = (bool) $db->setQuery($query)->loadResult();
+        } catch (ExecutionFailureException $e) {
+            return;
+        }
+
+        $query->clear();
+
+        // If preferences don't exist, insert.
+        if (!$exists && $authorised && isset($user['actionlogs'])) {
+            $notify  = (int) $user['actionlogs']['actionlogsNotify'];
+            $values  = [':userid', ':notify'];
+            $bind    = [$userid, $notify];
+            $columns = ['user_id', 'notify'];
+
+            $query->bind($values, $bind, ParameterType::INTEGER);
+
+            if (isset($user['actionlogs']['actionlogsExtensions'])) {
+                $values[]  = ':extension';
+                $columns[] = 'extensions';
+                $extension = json_encode($user['actionlogs']['actionlogsExtensions']);
+                $query->bind(':extension', $extension);
+            }
+
+            $query->insert($db->quoteName('#__action_logs_users'))
+                ->columns($db->quoteName($columns))
+                ->values(implode(',', $values));
+        } elseif ($exists && $authorised && isset($user['actionlogs'])) {
+            // Update preferences.
+            $notify = (int) $user['actionlogs']['actionlogsNotify'];
+            $values = [$db->quoteName('notify') . ' = :notify'];
+
+            $query->bind(':notify', $notify, ParameterType::INTEGER);
+
+            if (isset($user['actionlogs']['actionlogsExtensions'])) {
+                $values[]  = $db->quoteName('extensions') . ' = :extension';
+                $extension = json_encode($user['actionlogs']['actionlogsExtensions']);
+                $query->bind(':extension', $extension);
+            }
+
+            $query->update($db->quoteName('#__action_logs_users'))
+                ->set($values)
+                ->where($db->quoteName('user_id') . ' = :userid')
+                ->bind(':userid', $userid, ParameterType::INTEGER);
+        } elseif ($exists && !$authorised) {
+            // Remove preferences if user is not authorised.
+            $query->delete($db->quoteName('#__action_logs_users'))
+                ->where($db->quoteName('user_id') . ' = :userid')
+                ->bind(':userid', $userid, ParameterType::INTEGER);
+        } else {
+            return;
+        }
+
+        try {
+            $db->setQuery($query)->execute();
+        } catch (ExecutionFailureException $e) {
+            // Do nothing.
+        }
+    }
+
+    /**
+     * Removes user preferences
+     *
+     * Method is called after user data is deleted from the database
+     *
+     * @param   array    $user     Holds the user data
+     * @param   boolean  $success  True if user was successfully stored in the database
+     * @param   string   $msg      Message
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onUserAfterDelete($user, $success, $msg): void
+    {
+        if (!$success) {
+            return;
+        }
+
+        $db     = $this->getDatabase();
+        $userid = (int) $user['id'];
+
+        $query = $db->getQuery(true)
+            ->delete($db->quoteName('#__action_logs_users'))
+            ->where($db->quoteName('user_id') . ' = :userid')
+            ->bind(':userid', $userid, ParameterType::INTEGER);
+
+        try {
+            $db->setQuery($query)->execute();
+        } catch (ExecutionFailureException $e) {
+            // Do nothing.
+        }
+    }
+
+    /**
+     * Method to render a value.
+     *
+     * @param   integer|string  $value  The value (0 or 1).
+     *
+     * @return  string  The rendered value.
+     *
+     * @since   3.9.16
+     */
+    public static function renderActionlogsNotify($value)
+    {
+        return Text::_($value ? 'JYES' : 'JNO');
+    }
+
+    /**
+     * Method to render a list of extensions.
+     *
+     * @param   array|string  $extensions  Array of extensions or an empty string if none selected.
+     *
+     * @return  string  The rendered value.
+     *
+     * @since   3.9.16
+     */
+    public static function renderActionlogsExtensions($extensions)
+    {
+        // No extensions selected.
+        if (!$extensions) {
+            return Text::_('JNONE');
+        }
+
+        foreach ($extensions as &$extension) {
+            // Load extension language files and translate extension name.
+            ActionlogsHelper::loadTranslationFiles($extension);
+            $extension = Text::_($extension);
+        }
+
+        return implode(', ', $extensions);
+    }
+}

plugins/system/cache/cache.xml

@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_cache</name>
+	<author>Joomla! Project</author>
+	<creationDate>2007-02</creationDate>
+	<copyright>(C) 2007 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_CACHE_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Cache</namespace>
+	<files>
+		<folder plugin="cache">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_cache.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_cache.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="browsercache"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_CACHE_FIELD_BROWSERCACHE_LABEL"
+					default="0"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="exclude_menu_items"
+					type="menuitem"
+					label="PLG_CACHE_FIELD_EXCLUDE_MENU_ITEMS_LABEL"
+					multiple="multiple"
+					filter="intarray"
+					layout="joomla.form.field.groupedlist-fancy-select"
+				/>
+
+			</fieldset>
+			<fieldset name="advanced">
+				<field
+					name="exclude"
+					type="textarea"
+					label="PLG_CACHE_FIELD_EXCLUDE_LABEL"
+					description="PLG_CACHE_FIELD_EXCLUDE_DESC"
+					rows="15"
+					filter="raw"
+				/>
+
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/cache/services/provider.php

@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.cache
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Cache\CacheControllerFactoryInterface;
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\Profiler\Profiler;
+use Joomla\CMS\Router\SiteRouter;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Cache\Extension\Cache;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     * @since   4.2.0
+     */
+    public function register(Container $container)
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin                 = PluginHelper::getPlugin('system', 'cache');
+                $dispatcher             = $container->get(DispatcherInterface::class);
+                $documentFactory        = $container->get('document.factory');
+                $cacheControllerFactory = $container->get(CacheControllerFactoryInterface::class);
+                $profiler               = (\defined('JDEBUG') && JDEBUG) ? Profiler::getInstance('Application') : null;
+                $router                 = $container->has(SiteRouter::class) ? $container->get(SiteRouter::class) : null;
+
+                $plugin = new Cache($dispatcher, (array) $plugin, $documentFactory, $cacheControllerFactory, $profiler, $router);
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/cache/src/Extension/Cache.php

@@ -0,0 +1,382 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.cache
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Cache\Extension;
+
+use Joomla\CMS\Cache\CacheController;
+use Joomla\CMS\Cache\CacheControllerFactoryInterface;
+use Joomla\CMS\Document\FactoryInterface as DocumentFactoryInterface;
+use Joomla\CMS\Event\AbstractEvent;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\Profiler\Profiler;
+use Joomla\CMS\Router\SiteRouter;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Event\Event;
+use Joomla\Event\Priority;
+use Joomla\Event\SubscriberInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! Page Cache Plugin.
+ *
+ * @since  1.5
+ */
+final class Cache extends CMSPlugin implements SubscriberInterface
+{
+    /**
+     * Cache instance.
+     *
+     * @var    CacheController
+     * @since  1.5
+     */
+    private $cache;
+
+    /**
+     * The application's document factory interface
+     *
+     * @var   DocumentFactoryInterface
+     * @since 4.2.0
+     */
+    private $documentFactory;
+
+    /**
+     * Cache controller factory interface
+     *
+     * @var    CacheControllerFactoryInterface
+     * @since  4.2.0
+     */
+    private $cacheControllerFactory;
+
+    /**
+     * The application profiler, used when Debug Site is set to Yes in Global Configuration.
+     *
+     * @var    Profiler|null
+     * @since  4.2.0
+     */
+    private $profiler;
+
+    /**
+     * The frontend router, injected by the service provider.
+     *
+     * @var   SiteRouter|null
+     * @since 4.2.0
+     */
+    private $router;
+
+    /**
+     * Constructor
+     *
+     * @param   DispatcherInterface              $dispatcher                 The object to observe
+     * @param   array                            $config                     An optional associative
+     *                                                                       array of configuration
+     *                                                                       settings. Recognized key
+     *                                                                       values include 'name',
+     *                                                                       'group', 'params',
+     *                                                                       'language'
+     *                                                                       (this list is not meant
+     *                                                                       to be comprehensive).
+     * @param   DocumentFactoryInterface         $documentFactory            The application's
+     *                                                                       document factory
+     * @param   CacheControllerFactoryInterface  $cacheControllerFactory     Cache controller factory
+     * @param   Profiler|null                    $profiler                   The application profiler
+     * @param   SiteRouter|null                  $router                     The frontend router
+     *
+     * @since   4.2.0
+     */
+    public function __construct(
+        DispatcherInterface $dispatcher,
+        array $config,
+        DocumentFactoryInterface $documentFactory,
+        CacheControllerFactoryInterface $cacheControllerFactory,
+        ?Profiler $profiler,
+        ?SiteRouter $router
+    ) {
+        parent::__construct($dispatcher, $config);
+
+        $this->documentFactory        = $documentFactory;
+        $this->cacheControllerFactory = $cacheControllerFactory;
+        $this->profiler               = $profiler;
+        $this->router                 = $router;
+    }
+
+    /**
+     * Returns an array of CMS events this plugin will listen to and the respective handlers.
+     *
+     * @return  array
+     *
+     * @since   4.2.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        /**
+         * Note that onAfterRender and onAfterRespond must be the last handlers to run for this
+         * plugin to operate as expected. These handlers put pages into cache. We must make sure
+         * that a. the page SHOULD be cached and b. we are caching the complete page, as it's
+         * output to the browser.
+         */
+        return [
+            'onAfterRoute'   => 'onAfterRoute',
+            'onAfterRender'  => ['onAfterRender', Priority::LOW],
+            'onAfterRespond' => ['onAfterRespond', Priority::LOW],
+        ];
+    }
+
+    /**
+     * Returns a cached page if the current URL exists in the cache.
+     *
+     * @param   Event  $event  The Joomla event being handled
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onAfterRoute(Event $event)
+    {
+        if (!$this->appStateSupportsCaching()) {
+            return;
+        }
+
+        // If any `pagecache` plugins return false for onPageCacheSetCaching, do not use the cache.
+        PluginHelper::importPlugin('pagecache');
+
+        $results = $this->getApplication()->triggerEvent('onPageCacheSetCaching');
+
+        $this->getCacheController()->setCaching(!\in_array(false, $results, true));
+
+        $data = $this->getCacheController()->get($this->getCacheKey());
+
+        if ($data === false) {
+            // No cached data.
+            return;
+        }
+
+        // Set the page content from the cache and output it to the browser.
+        $this->getApplication()->setBody($data);
+
+        echo $this->getApplication()->toString((bool) $this->getApplication()->get('gzip'));
+
+        // Mark afterCache in debug and run debug onAfterRespond events, e.g. show Joomla Debug Console if debug is active.
+        if (JDEBUG) {
+            // Create a document instance and load it into the application.
+            $document = $this->documentFactory
+                ->createDocument($this->getApplication()->getInput()->get('format', 'html'));
+            $this->getApplication()->loadDocument($document);
+
+            if ($this->profiler) {
+                $this->profiler->mark('afterCache');
+            }
+
+            $this->getDispatcher()->dispatch('onAfterRespond', AbstractEvent::create(
+                'onAfterRespond',
+                [
+                    'subject' => $this->getApplication(),
+                ]
+            ));
+        }
+
+        // Closes the application.
+        $this->getApplication()->close();
+    }
+
+    /**
+     * Does the current application state allow for caching?
+     *
+     * The following conditions must be met:
+     * * This is the frontend application. This plugin does not apply to other applications.
+     * * This is a GET request. This plugin does not apply to POST, PUT etc.
+     * * There is no currently logged in user (pages might have user–specific content).
+     * * The message queue is empty.
+     *
+     * The first two tests are cached to make early returns possible; these conditions cannot change
+     * throughout the lifetime of the request.
+     *
+     * The other two tests MUST NOT be cached because auto–login plugins may fire anytime within
+     * the application lifetime logging in a user and messages can be generated anytime within the
+     * application's lifetime.
+     *
+     * @return  boolean
+     * @since   4.2.0
+     */
+    private function appStateSupportsCaching(): bool
+    {
+        static $isSite = null;
+        static $isGET  = null;
+
+        if ($isSite === null) {
+            $isSite = $this->getApplication()->isClient('site');
+            $isGET  = $this->getApplication()->getInput()->getMethod() === 'GET';
+        }
+
+        // Boolean short–circuit evaluation means this returns fast false when $isSite is false.
+        return $isSite
+            && $isGET
+            && $this->getApplication()->getIdentity()->guest
+            && empty($this->getApplication()->getMessageQueue());
+    }
+
+    /**
+     * Get the cache controller
+     *
+     * @return  CacheController
+     * @since   4.2.0
+     */
+    private function getCacheController(): CacheController
+    {
+        if (!empty($this->cache)) {
+            return $this->cache;
+        }
+
+        // Set the cache options.
+        $options = [
+            'defaultgroup' => 'page',
+            'browsercache' => $this->params->get('browsercache', 0),
+            'caching'      => false,
+        ];
+
+        // Instantiate cache with previous options.
+        $this->cache = $this->cacheControllerFactory->createCacheController('page', $options);
+
+        return $this->cache;
+    }
+
+    /**
+     * Get a cache key for the current page based on the url and possible other factors.
+     *
+     * @return  string
+     *
+     * @since   3.7
+     */
+    private function getCacheKey(): string
+    {
+        static $key;
+
+        if (!$key) {
+            PluginHelper::importPlugin('pagecache');
+
+            $parts   = $this->getApplication()->triggerEvent('onPageCacheGetKey');
+            $parts[] = Uri::getInstance()->toString();
+
+            $key = md5(serialize($parts));
+        }
+
+        return $key;
+    }
+
+    /**
+     * After Render Event. Check whether the current page is excluded from cache.
+     *
+     * @param   Event  $event  The CMS event we are handling.
+     *
+     * @return  void
+     *
+     * @since   3.9.12
+     */
+    public function onAfterRender(Event $event)
+    {
+        if (!$this->appStateSupportsCaching() || $this->getCacheController()->getCaching() === false) {
+            return;
+        }
+
+        if ($this->isExcluded() === true) {
+            $this->getCacheController()->setCaching(false);
+
+            return;
+        }
+
+        // Disable compression before caching the page.
+        $this->getApplication()->set('gzip', false);
+    }
+
+    /**
+     * Check if the page is excluded from the cache or not.
+     *
+     * @return   boolean  True if the page is excluded else false
+     *
+     * @since    3.5
+     */
+    private function isExcluded(): bool
+    {
+        // Check if menu items have been excluded.
+        $excludedMenuItems = $this->params->get('exclude_menu_items', []);
+
+        if ($excludedMenuItems) {
+            // Get the current menu item.
+            $active = $this->getApplication()->getMenu()->getActive();
+
+            if ($active && $active->id && \in_array((int) $active->id, (array) $excludedMenuItems)) {
+                return true;
+            }
+        }
+
+        // Check if regular expressions are being used.
+        $exclusions = $this->params->get('exclude', '');
+
+        if ($exclusions) {
+            // Convert the exclusions into a normalised array
+            $exclusions       = str_replace(["\r\n", "\r"], "\n", $exclusions);
+            $exclusions       = explode("\n", $exclusions);
+            $filterExpression = function ($x) {
+                return $x !== '';
+            };
+            $exclusions       = array_filter($exclusions, $filterExpression);
+
+            // Gets the internal (non-SEF) and the external (possibly SEF) URIs.
+            $internalUrl = '/index.php?'
+                . Uri::getInstance()->buildQuery($this->router->getVars());
+            $externalUrl = Uri::getInstance()->toString();
+
+            $reduceCallback
+                = function (bool $carry, string $exclusion) use ($internalUrl, $externalUrl) {
+                    // Test both external and internal URIs
+                    return $carry && preg_match(
+                        '#' . $exclusion . '#i',
+                        $externalUrl . ' ' . $internalUrl,
+                        $match
+                    );
+                };
+            $excluded       = array_reduce($exclusions, $reduceCallback, false);
+
+            if ($excluded) {
+                return true;
+            }
+        }
+
+        // If any pagecache plugins return true for onPageCacheIsExcluded, exclude.
+        PluginHelper::importPlugin('pagecache');
+
+        $results = $this->getApplication()->triggerEvent('onPageCacheIsExcluded');
+
+        return \in_array(true, $results, true);
+    }
+
+    /**
+     * After Respond Event. Stores page in cache.
+     *
+     * @param   Event  $event  The application event we are handling.
+     *
+     * @return  void
+     *
+     * @since   1.5
+     */
+    public function onAfterRespond(Event $event)
+    {
+        if (!$this->appStateSupportsCaching() || $this->getCacheController()->getCaching() === false) {
+            return;
+        }
+
+        // Saves current page in cache.
+        $this->getCacheController()->store($this->getApplication()->getBody(), $this->getCacheKey());
+    }
+}

plugins/system/debug/debug.xml

@@ -0,0 +1,262 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_debug</name>
+	<author>Joomla! Project</author>
+	<creationDate>2006-12</creationDate>
+	<copyright>(C) 2006 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_DEBUG_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Debug</namespace>
+	<files>
+		<folder plugin="debug">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_debug.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_debug.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="refresh_assets"
+					type="radio"
+					label="PLG_DEBUG_FIELD_REFRESH_ASSETS_LABEL"
+					description="PLG_DEBUG_FIELD_REFRESH_ASSETS_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="filter_groups"
+					type="usergrouplist"
+					label="PLG_DEBUG_FIELD_ALLOWED_GROUPS_LABEL"
+					multiple="true"
+					layout="joomla.form.field.list-fancy-select"
+					filter="intarray"
+				/>
+
+				<field
+					name="memory"
+					type="radio"
+					label="PLG_DEBUG_FIELD_MEMORY_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="request"
+					type="radio"
+					label="PLG_DEBUG_FIELD_REQUEST_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="session"
+					type="radio"
+					label="PLG_DEBUG_FIELD_SESSION_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="profile"
+					type="radio"
+					label="PLG_DEBUG_FIELD_PROFILING_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="queries"
+					type="radio"
+					label="PLG_DEBUG_FIELD_QUERIES_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="query_traces"
+					type="radio"
+					label="PLG_DEBUG_FIELD_QUERY_TRACES_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="queries:1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="query_profiles"
+					type="radio"
+					label="PLG_DEBUG_FIELD_QUERY_PROFILES_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="queries:1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="query_explains"
+					type="radio"
+					label="PLG_DEBUG_FIELD_QUERY_EXPLAINS_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="queries:1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="track_request_history"
+					type="radio"
+					label="PLG_DEBUG_FIELD_TRACK_REQUEST_HISTORY_LABEL"
+					description="PLG_DEBUG_FIELD_TRACK_REQUEST_HISTORY_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+			</fieldset>
+
+			<fieldset
+				name="language"
+				label="PLG_DEBUG_LANGUAGE_FIELDSET_LABEL"
+				>
+
+				<field
+					name="language_errorfiles"
+					type="radio"
+					label="PLG_DEBUG_FIELD_LANGUAGE_ERRORFILES_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="language_files"
+					type="radio"
+					label="PLG_DEBUG_FIELD_LANGUAGE_FILES_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="language_strings"
+					type="radio"
+					label="PLG_DEBUG_FIELD_LANGUAGE_STRING_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="strip-first"
+					type="radio"
+					label="PLG_DEBUG_FIELD_STRIP_FIRST_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="strip-prefix"
+					type="textarea"
+					label="PLG_DEBUG_FIELD_STRIP_PREFIX_LABEL"
+					description="PLG_DEBUG_FIELD_STRIP_PREFIX_DESC"
+					cols="30"
+					rows="4"
+				/>
+
+				<field
+					name="strip-suffix"
+					type="textarea"
+					label="PLG_DEBUG_FIELD_STRIP_SUFFIX_LABEL"
+					description="PLG_DEBUG_FIELD_STRIP_SUFFIX_DESC"
+					cols="30"
+					rows="4"
+				/>
+			</fieldset>
+
+			<fieldset
+				name="logging"
+				label="PLG_DEBUG_LOGGING_FIELDSET_LABEL"
+				>
+				<field
+					name="logs"
+					type="radio"
+					label="PLG_DEBUG_FIELD_LOGS_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					>
+					<option value="0">JHIDE</option>
+					<option value="1">JSHOW</option>
+				</field>
+
+				<field
+					name="log-deprecated-core"
+					type="radio"
+					label="PLG_DEBUG_FIELD_LOG_DEPRECATED_CORE_LABEL"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					showon="logs:1"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/debug/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.debug
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Debug\Extension\Debug;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                return new Debug(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'debug'),
+                    Factory::getApplication(),
+                    $container->get(DatabaseInterface::class)
+                );
+            }
+        );
+    }
+};

plugins/system/debug/src/AbstractDataCollector.php

@@ -0,0 +1,113 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug;
+
+use DebugBar\DataCollector\DataCollector;
+use DebugBar\DataCollector\Renderable;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * AbstractDataCollector
+ *
+ * @since  4.0.0
+ */
+abstract class AbstractDataCollector extends DataCollector implements Renderable
+{
+    /**
+     * Parameters.
+     *
+     * @var   Registry
+     * @since 4.0.0
+     */
+    protected $params;
+
+    /**
+     * The default formatter.
+     *
+     * @var   DataFormatter
+     * @since 4.0.0
+     */
+    private static $defaultDataFormatter;
+
+    /**
+     * AbstractDataCollector constructor.
+     *
+     * @param   Registry  $params  Parameters.
+     *
+     * @since 4.0.0
+     */
+    public function __construct(Registry $params)
+    {
+        $this->params = $params;
+    }
+
+    /**
+     * Get a data formatter.
+     *
+     * @since  4.0.0
+     * @return DataFormatter
+     */
+    public function getDataFormatter(): DataFormatter
+    {
+        if ($this->dataFormater === null) {
+            $this->dataFormater = self::getDefaultDataFormatter();
+        }
+
+        return $this->dataFormater;
+    }
+
+    /**
+     * Returns the default data formatter
+     *
+     * @since  4.0.0
+     * @return DataFormatter
+     */
+    public static function getDefaultDataFormatter(): DataFormatter
+    {
+        if (self::$defaultDataFormatter === null) {
+            self::$defaultDataFormatter = new DataFormatter();
+        }
+
+        return self::$defaultDataFormatter;
+    }
+
+    /**
+     * Strip the Joomla! root path.
+     *
+     * @param   string  $path  The path.
+     *
+     * @return string
+     *
+     * @since  4.0.0
+     */
+    public function formatPath($path): string
+    {
+        return $this->getDataFormatter()->formatPath($path);
+    }
+
+    /**
+     * Format a string from back trace.
+     *
+     * @param   array  $call  The array to format
+     *
+     * @return string
+     *
+     * @since  4.0.0
+     */
+    public function formatCallerInfo(array $call): string
+    {
+        return $this->getDataFormatter()->formatCallerInfo($call);
+    }
+}

plugins/system/debug/src/DataCollector/InfoCollector.php

@@ -0,0 +1,217 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\AssetProvider;
+use Joomla\CMS\Application\AdministratorApplication;
+use Joomla\CMS\Application\SiteApplication;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Uri\Uri;
+use Joomla\CMS\User\User;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+use Joomla\Registry\Registry;
+use Psr\Http\Message\ResponseInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * InfoDataCollector
+ *
+ * @since  4.0.0
+ */
+class InfoCollector extends AbstractDataCollector implements AssetProvider
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'info';
+
+    /**
+     * Request ID.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $requestId;
+
+    /**
+     * InfoDataCollector constructor.
+     *
+     * @param   Registry  $params     Parameters
+     * @param   string    $requestId  Request ID
+     *
+     * @since  4.0.0
+     */
+    public function __construct(Registry $params, $requestId)
+    {
+        $this->requestId = $requestId;
+
+        parent::__construct($params);
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     * @return array
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'info' => [
+                'icon'    => 'info-circle',
+                'title'   => 'J! Info',
+                'widget'  => 'PhpDebugBar.Widgets.InfoWidget',
+                'map'     => $this->name,
+                'default' => '{}',
+            ],
+        ];
+    }
+
+    /**
+     * Returns an array with the following keys:
+     *  - base_path
+     *  - base_url
+     *  - css: an array of filenames
+     *  - js: an array of filenames
+     *
+     * @since  4.0.0
+     * @return array
+     */
+    public function getAssets(): array
+    {
+        return [
+            'js'  => Uri::root(true) . '/media/plg_system_debug/widgets/info/widget.min.js',
+            'css' => Uri::root(true) . '/media/plg_system_debug/widgets/info/widget.min.css',
+        ];
+    }
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.0.0
+     *
+     * @return array Collected data
+     */
+    public function collect(): array
+    {
+        /** @type SiteApplication|AdministratorApplication $application */
+        $application = Factory::getApplication();
+
+        $model = $application->bootComponent('com_admin')
+            ->getMVCFactory()->createModel('Sysinfo', 'Administrator');
+
+        return [
+            'phpVersion'    => PHP_VERSION,
+            'joomlaVersion' => JVERSION,
+            'requestId'     => $this->requestId,
+            'identity'      => $this->getIdentityInfo($application->getIdentity()),
+            'response'      => $this->getResponseInfo($application->getResponse()),
+            'template'      => $this->getTemplateInfo($application->getTemplate(true)),
+            'database'      => $this->getDatabaseInfo($model->getInfo()),
+        ];
+    }
+
+    /**
+     * Get Identity info.
+     *
+     * @param   User  $identity  The identity.
+     *
+     * @since 4.0.0
+     *
+     * @return array
+     */
+    private function getIdentityInfo(User $identity): array
+    {
+        if (!$identity->id) {
+            return ['type' => 'guest'];
+        }
+
+        return [
+            'type'     => 'user',
+            'id'       => $identity->id,
+            'name'     => $identity->name,
+            'username' => $identity->username,
+        ];
+    }
+
+    /**
+     * Get response info.
+     *
+     * @param   ResponseInterface  $response  The response.
+     *
+     * @since 4.0.0
+     *
+     * @return array
+     */
+    private function getResponseInfo(ResponseInterface $response): array
+    {
+        return [
+            'status_code' => $response->getStatusCode(),
+        ];
+    }
+
+    /**
+     * Get template info.
+     *
+     * @param   object  $template  The template.
+     *
+     * @since 4.0.0
+     *
+     * @return array
+     */
+    private function getTemplateInfo($template): array
+    {
+        return [
+            'template' => $template->template ?? '',
+            'home'     => $template->home ?? '',
+            'id'       => $template->id ?? '',
+        ];
+    }
+
+    /**
+     * Get database info.
+     *
+     * @param   array  $info  General information.
+     *
+     * @since 4.0.0
+     *
+     * @return array
+     */
+    private function getDatabaseInfo(array $info): array
+    {
+        return [
+            'dbserver'               => $info['dbserver'] ?? '',
+            'dbversion'              => $info['dbversion'] ?? '',
+            'dbcollation'            => $info['dbcollation'] ?? '',
+            'dbconnectioncollation'  => $info['dbconnectioncollation'] ?? '',
+            'dbconnectionencryption' => $info['dbconnectionencryption'] ?? '',
+            'dbconnencryptsupported' => $info['dbconnencryptsupported'] ?? '',
+        ];
+    }
+}

plugins/system/debug/src/DataCollector/LanguageErrorsCollector.php

@@ -0,0 +1,153 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\AssetProvider;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * LanguageErrorsDataCollector
+ *
+ * @since  4.0.0
+ */
+class LanguageErrorsCollector extends AbstractDataCollector implements AssetProvider
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'languageErrors';
+
+    /**
+     * The count.
+     *
+     * @var   integer
+     * @since 4.0.0
+     */
+    private $count = 0;
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.0.0
+     *
+     * @return array Collected data
+     */
+    public function collect(): array
+    {
+        return [
+            'data' => [
+                'files'      => $this->getData(),
+                'jroot'      => JPATH_ROOT,
+                'xdebugLink' => $this->getXdebugLinkTemplate(),
+            ],
+            'count' => $this->getCount(),
+        ];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     *
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'errors' => [
+                'icon'    => 'warning',
+                'widget'  => 'PhpDebugBar.Widgets.languageErrorsWidget',
+                'map'     => $this->name . '.data',
+                'default' => '',
+            ],
+            'errors:badge' => [
+                'map'     => $this->name . '.count',
+                'default' => 'null',
+            ],
+        ];
+    }
+
+    /**
+     * Returns an array with the following keys:
+     *  - base_path
+     *  - base_url
+     *  - css: an array of filenames
+     *  - js: an array of filenames
+     *
+     * @since  4.0.0
+     * @return array
+     */
+    public function getAssets()
+    {
+        return [
+            'js'  => Uri::root(true) . '/media/plg_system_debug/widgets/languageErrors/widget.min.js',
+            'css' => Uri::root(true) . '/media/plg_system_debug/widgets/languageErrors/widget.min.css',
+        ];
+    }
+
+    /**
+     * Collect data.
+     *
+     * @return array
+     *
+     * @since 4.0.0
+     */
+    private function getData(): array
+    {
+        $errorFiles = Factory::getLanguage()->getErrorFiles();
+        $errors     = [];
+
+        if (\count($errorFiles)) {
+            foreach ($errorFiles as $file => $lines) {
+                foreach ($lines as $line) {
+                    $errors[] = [$file, $line];
+                    $this->count++;
+                }
+            }
+        }
+
+        return $errors;
+    }
+
+    /**
+     * Get a count value.
+     *
+     * @return int
+     *
+     * @since 4.0.0
+     */
+    private function getCount(): int
+    {
+        return $this->count;
+    }
+}

plugins/system/debug/src/DataCollector/LanguageFilesCollector.php

@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\AssetProvider;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * LanguageFilesDataCollector
+ *
+ * @since  4.0.0
+ */
+class LanguageFilesCollector extends AbstractDataCollector implements AssetProvider
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'languageFiles';
+
+    /**
+     * The count.
+     *
+     * @var   integer
+     * @since 4.0.0
+     */
+    private $count = 0;
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.0.0
+     *
+     * @return array Collected data
+     */
+    public function collect(): array
+    {
+        $paths  = Factory::getLanguage()->getPaths();
+        $loaded = [];
+
+        foreach ($paths as $extension => $files) {
+            $loaded[$extension] = [];
+
+            foreach ($files as $file => $status) {
+                $loaded[$extension][$file] = $status;
+
+                if ($status) {
+                    $this->count++;
+                }
+            }
+        }
+
+        return [
+            'loaded'     => $loaded,
+            'xdebugLink' => $this->getXdebugLinkTemplate(),
+            'jroot'      => JPATH_ROOT,
+            'count'      => $this->count,
+        ];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     *
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'loaded' => [
+                'icon'    => 'language',
+                'widget'  => 'PhpDebugBar.Widgets.languageFilesWidget',
+                'map'     => $this->name,
+                'default' => '[]',
+            ],
+            'loaded:badge' => [
+                'map'     => $this->name . '.count',
+                'default' => 'null',
+            ],
+        ];
+    }
+
+    /**
+     * Returns an array with the following keys:
+     *  - base_path
+     *  - base_url
+     *  - css: an array of filenames
+     *  - js: an array of filenames
+     *
+     * @since  4.0.0
+     * @return array
+     */
+    public function getAssets(): array
+    {
+        return [
+            'js'  => Uri::root(true) . '/media/plg_system_debug/widgets/languageFiles/widget.min.js',
+            'css' => Uri::root(true) . '/media/plg_system_debug/widgets/languageFiles/widget.min.css',
+        ];
+    }
+}

plugins/system/debug/src/DataCollector/LanguageStringsCollector.php

@@ -0,0 +1,189 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\AssetProvider;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Language\Language;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * LanguageStringsDataCollector
+ *
+ * @since  4.0.0
+ */
+class LanguageStringsCollector extends AbstractDataCollector implements AssetProvider
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'languageStrings';
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.0.0
+     *
+     * @return array Collected data
+     */
+    public function collect(): array
+    {
+        return [
+            'data'  => $this->getData(),
+            'count' => $this->getCount(),
+        ];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     *
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'untranslated' => [
+                'icon'    => 'question-circle',
+                'widget'  => 'PhpDebugBar.Widgets.languageStringsWidget',
+                'map'     => $this->name . '.data',
+                'default' => '',
+            ],
+            'untranslated:badge' => [
+                'map'     => $this->name . '.count',
+                'default' => 'null',
+            ],
+        ];
+    }
+
+    /**
+     * Returns an array with the following keys:
+     *  - base_path
+     *  - base_url
+     *  - css: an array of filenames
+     *  - js: an array of filenames
+     *
+     * @since  4.0.0
+     * @return array
+     */
+    public function getAssets(): array
+    {
+        return [
+            'js'  => Uri::root(true) . '/media/plg_system_debug/widgets/languageStrings/widget.min.js',
+            'css' => Uri::root(true) . '/media/plg_system_debug/widgets/languageStrings/widget.min.css',
+        ];
+    }
+
+    /**
+     * Collect data.
+     *
+     * @return array
+     *
+     * @since 4.0.0
+     */
+    private function getData(): array
+    {
+        $orphans = Factory::getLanguage()->getOrphans();
+
+        $data = [];
+
+        foreach ($orphans as $orphan => $occurrences) {
+            $data[$orphan] = [];
+
+            foreach ($occurrences as $occurrence) {
+                $item = [];
+
+                $item['string'] = $occurrence['string'] ?? 'n/a';
+                $item['trace']  = [];
+                $item['caller'] = '';
+
+                if (isset($occurrence['trace'])) {
+                    $cnt            = 0;
+                    $trace          = [];
+                    $callerLocation = '';
+
+                    array_shift($occurrence['trace']);
+
+                    foreach ($occurrence['trace'] as $i => $stack) {
+                        $class = $stack['class'] ?? '';
+                        $file  = $stack['file'] ?? '';
+                        $line  = $stack['line'] ?? '';
+
+                        $caller   = $this->formatCallerInfo($stack);
+                        $location = $file && $line ? "$file:$line" : 'same';
+
+                        $isCaller = 0;
+
+                        if (!$callerLocation && $class !== Language::class && !strpos($file, 'Text.php')) {
+                            $callerLocation = $location;
+                            $isCaller       = 1;
+                        }
+
+                        $trace[] = [
+                            \count($occurrence['trace']) - $cnt,
+                            $isCaller,
+                            $caller,
+                            $file,
+                            $line,
+                        ];
+
+                        $cnt++;
+                    }
+
+                    $item['trace']  = $trace;
+                    $item['caller'] = $callerLocation;
+                }
+
+                $data[$orphan][] = $item;
+            }
+        }
+
+        return [
+            'orphans'    => $data,
+            'jroot'      => JPATH_ROOT,
+            'xdebugLink' => $this->getXdebugLinkTemplate(),
+        ];
+    }
+
+    /**
+     * Get a count value.
+     *
+     * @return integer
+     *
+     * @since 4.0.0
+     */
+    private function getCount(): int
+    {
+        return \count(Factory::getLanguage()->getOrphans());
+    }
+}

plugins/system/debug/src/DataCollector/MemoryCollector.php

@@ -0,0 +1,151 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Collects info about the request duration as well as providing
+ * a way to log duration of any operations
+ *
+ * @since  4.4.0
+ */
+class MemoryCollector extends AbstractDataCollector
+{
+    /**
+     * @var   boolean
+     * @since 4.4.0
+     */
+    protected $realUsage = false;
+
+    /**
+     * @var    float
+     * @since 4.4.0
+     */
+    protected $peakUsage = 0;
+
+    /**
+     * @param   Registry  $params Parameters.
+     * @param   float     $peakUsage
+     * @param   boolean   $realUsage
+     *
+     * @since 4.4.0
+     */
+    public function __construct(Registry $params, $peakUsage = null, $realUsage = null)
+    {
+        parent::__construct($params);
+
+        if ($peakUsage !== null) {
+            $this->peakUsage = $peakUsage;
+        }
+
+        if ($realUsage !== null) {
+            $this->realUsage = $realUsage;
+        }
+    }
+
+    /**
+     * Returns whether total allocated memory page size is used instead of actual used memory size
+     * by the application.  See $real_usage parameter on memory_get_peak_usage for details.
+     *
+     * @return boolean
+     *
+     * @since 4.4.0
+     */
+    public function getRealUsage()
+    {
+        return $this->realUsage;
+    }
+
+    /**
+     * Sets whether total allocated memory page size is used instead of actual used memory size
+     * by the application.  See $real_usage parameter on memory_get_peak_usage for details.
+     *
+     * @param boolean $realUsage
+     *
+     * @since 4.4.0
+     */
+    public function setRealUsage($realUsage)
+    {
+        $this->realUsage = $realUsage;
+    }
+
+    /**
+     * Returns the peak memory usage
+     *
+     * @return integer
+     *
+     * @since 4.4.0
+     */
+    public function getPeakUsage()
+    {
+        return $this->peakUsage;
+    }
+
+    /**
+     * Updates the peak memory usage value
+     *
+     * @since 4.4.0
+     */
+    public function updatePeakUsage()
+    {
+        if ($this->peakUsage === null) {
+            $this->peakUsage = memory_get_peak_usage($this->realUsage);
+        }
+    }
+
+    /**
+     * @return array
+     *
+     * @since 4.4.0
+     */
+    public function collect()
+    {
+        $this->updatePeakUsage();
+
+        return [
+            'peak_usage'     => $this->peakUsage,
+            'peak_usage_str' => $this->getDataFormatter()->formatBytes($this->peakUsage, 3),
+        ];
+    }
+
+    /**
+     * @return string
+     *
+     * @since 4.4.0
+     */
+    public function getName()
+    {
+        return 'memory';
+    }
+
+    /**
+     * @return array
+     *
+     * @since 4.4.0
+     */
+    public function getWidgets()
+    {
+        return [
+            'memory' => [
+                'icon'    => 'cogs',
+                'tooltip' => 'Memory Usage',
+                'map'     => 'memory.peak_usage_str',
+                'default' => "'0B'",
+            ],
+        ];
+    }
+}

plugins/system/debug/src/DataCollector/ProfileCollector.php

@@ -0,0 +1,342 @@
+<?php
+
+/**
+ * This file is part of the DebugBar package.
+ *
+ * @copyright  (c) 2013 Maxime Bouroumeau-Fuseau
+ * @license    For the full copyright and license information, please view the LICENSE
+ *             file that was distributed with this source code.
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DebugBarException;
+use Joomla\CMS\Profiler\Profiler;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Collects info about the request duration as well as providing
+ * a way to log duration of any operations
+ *
+ * @since  version
+ */
+class ProfileCollector extends AbstractDataCollector
+{
+    /**
+     * Request start time.
+     *
+     * @var   float
+     * @since 4.0.0
+     */
+    protected $requestStartTime;
+
+    /**
+     * Request end time.
+     *
+     * @var   float
+     * @since 4.0.0
+     */
+    protected $requestEndTime;
+
+    /**
+     * Started measures.
+     *
+     * @var array
+     * @since  4.0.0
+     */
+    protected $startedMeasures = [];
+
+    /**
+     * Measures.
+     *
+     * @var array
+     * @since  4.0.0
+     */
+    protected $measures = [];
+
+    /**
+     * Constructor.
+     *
+     * @param   Registry  $params  Parameters.
+     *
+     * @since 4.0.0
+     */
+    public function __construct(Registry $params)
+    {
+        if (isset($_SERVER['REQUEST_TIME_FLOAT'])) {
+            $this->requestStartTime = $_SERVER['REQUEST_TIME_FLOAT'];
+        } else {
+            $this->requestStartTime = microtime(true);
+        }
+
+        parent::__construct($params);
+    }
+
+    /**
+     * Starts a measure.
+     *
+     * @param   string       $name       Internal name, used to stop the measure
+     * @param   string|null  $label      Public name
+     * @param   string|null  $collector  The source of the collector
+     *
+     * @return void
+     *
+     * @since  4.0.0
+     */
+    public function startMeasure($name, $label = null, $collector = null)
+    {
+        $start = microtime(true);
+
+        $this->startedMeasures[$name] = [
+            'label'     => $label ?: $name,
+            'start'     => $start,
+            'collector' => $collector,
+        ];
+    }
+
+    /**
+     * Check a measure exists
+     *
+     * @param   string  $name  Group name.
+     *
+     * @return bool
+     *
+     * @since  4.0.0
+     */
+    public function hasStartedMeasure($name): bool
+    {
+        return isset($this->startedMeasures[$name]);
+    }
+
+    /**
+     * Stops a measure.
+     *
+     * @param   string  $name    Measurement name.
+     * @param   array   $params  Parameters
+     *
+     * @return void
+     *
+     * @since  4.0.0
+     *
+     * @throws DebugBarException
+     */
+    public function stopMeasure($name, array $params = [])
+    {
+        $end = microtime(true);
+
+        if (!$this->hasStartedMeasure($name)) {
+            throw new DebugBarException("Failed stopping measure '$name' because it hasn't been started");
+        }
+
+        $this->addMeasure($this->startedMeasures[$name]['label'], $this->startedMeasures[$name]['start'], $end, $params, $this->startedMeasures[$name]['collector']);
+
+        unset($this->startedMeasures[$name]);
+    }
+
+    /**
+     * Adds a measure
+     *
+     * @param   string       $label      A label.
+     * @param   float        $start      Start of request.
+     * @param   float        $end        End of request.
+     * @param   array        $params     Parameters.
+     * @param   string|null  $collector  A collector.
+     *
+     * @return void
+     *
+     * @since  4.0.0
+     */
+    public function addMeasure($label, $start, $end, array $params = [], $collector = null)
+    {
+        $this->measures[] = [
+            'label'          => $label,
+            'start'          => $start,
+            'relative_start' => $start - $this->requestStartTime,
+            'end'            => $end,
+            'relative_end'   => $end - $this->requestEndTime,
+            'duration'       => $end - $start,
+            'duration_str'   => $this->getDataFormatter()->formatDuration($end - $start),
+            'params'         => $params,
+            'collector'      => $collector,
+        ];
+    }
+
+    /**
+     * Utility function to measure the execution of a Closure
+     *
+     * @param   string       $label      A label.
+     * @param   \Closure     $closure    A closure.
+     * @param   string|null  $collector  A collector.
+     *
+     * @return void
+     *
+     * @since  4.0.0
+     */
+    public function measure($label, \Closure $closure, $collector = null)
+    {
+        $name = spl_object_hash($closure);
+        $this->startMeasure($name, $label, $collector);
+        $result = $closure();
+        $params = \is_array($result) ? $result : [];
+        $this->stopMeasure($name, $params);
+    }
+
+    /**
+     * Returns an array of all measures
+     *
+     * @return array
+     *
+     * @since  4.0.0
+     */
+    public function getMeasures(): array
+    {
+        return $this->measures;
+    }
+
+    /**
+     * Returns the request start time
+     *
+     * @return float
+     *
+     * @since  4.0.0
+     */
+    public function getRequestStartTime(): float
+    {
+        return $this->requestStartTime;
+    }
+
+    /**
+     * Returns the request end time
+     *
+     * @return float
+     *
+     * @since  4.0.0
+     */
+    public function getRequestEndTime(): float
+    {
+        return $this->requestEndTime;
+    }
+
+    /**
+     * Returns the duration of a request
+     *
+     * @return float
+     *
+     * @since  4.0.0
+     */
+    public function getRequestDuration(): float
+    {
+        if ($this->requestEndTime !== null) {
+            return $this->requestEndTime - $this->requestStartTime;
+        }
+
+        return microtime(true) - $this->requestStartTime;
+    }
+
+    /**
+     * Sets request end time.
+     *
+     * @param   float  $time  Request end time.
+     *
+     * @return $this
+     *
+     * @since  4.4.0
+     */
+    public function setRequestEndTime($time): self
+    {
+        $this->requestEndTime = $time;
+
+        return $this;
+    }
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @return array Collected data
+     *
+     * @since  4.0.0
+     */
+    public function collect(): array
+    {
+        $this->requestEndTime = $this->requestEndTime ?? microtime(true);
+
+        $start = $this->requestStartTime;
+
+        $marks = Profiler::getInstance('Application')->getMarks();
+
+        foreach ($marks as $mark) {
+            $mem   = $this->getDataFormatter()->formatBytes(abs($mark->memory) * 1048576);
+            $label = $mark->label . " ($mem)";
+            $end   = $start + $mark->time / 1000;
+            $this->addMeasure($label, $start, $end);
+            $start = $end;
+        }
+
+        foreach (array_keys($this->startedMeasures) as $name) {
+            $this->stopMeasure($name);
+        }
+
+        usort(
+            $this->measures,
+            function ($a, $b) {
+                if ($a['start'] === $b['start']) {
+                    return 0;
+                }
+
+                return $a['start'] < $b['start'] ? -1 : 1;
+            }
+        );
+
+        return [
+            'start'        => $this->requestStartTime,
+            'end'          => $this->requestEndTime,
+            'duration'     => $this->getRequestDuration(),
+            'duration_str' => $this->getDataFormatter()->formatDuration($this->getRequestDuration()),
+            'measures'     => array_values($this->measures),
+            'rawMarks'     => $marks,
+        ];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @return string
+     *
+     * @since  4.0.0
+     */
+    public function getName(): string
+    {
+        return 'profile';
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @return array
+     *
+     * @since  4.0.0
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'profileTime' => [
+                'icon'    => 'clock-o',
+                'tooltip' => 'Request Duration',
+                'map'     => 'profile.duration_str',
+                'default' => "'0ms'",
+            ],
+            'profile' => [
+                'icon'    => 'clock-o',
+                'widget'  => 'PhpDebugBar.Widgets.TimelineWidget',
+                'map'     => 'profile',
+                'default' => '{}',
+            ],
+        ];
+    }
+}

plugins/system/debug/src/DataCollector/QueryCollector.php

@@ -0,0 +1,258 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\AssetProvider;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Database\Monitor\DebugMonitor;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * QueryDataCollector
+ *
+ * @since  4.0.0
+ */
+class QueryCollector extends AbstractDataCollector implements AssetProvider
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'queries';
+
+    /**
+     * The query monitor.
+     *
+     * @var    DebugMonitor
+     * @since  4.0.0
+     */
+    private $queryMonitor;
+
+    /**
+     * Profile data.
+     *
+     * @var   array
+     * @since 4.0.0
+     */
+    private $profiles;
+
+    /**
+     * Explain data.
+     *
+     * @var   array
+     * @since 4.0.0
+     */
+    private $explains;
+
+    /**
+     * Accumulated Duration.
+     *
+     * @var   integer
+     * @since 4.0.0
+     */
+    private $accumulatedDuration = 0;
+
+    /**
+     * Accumulated Memory.
+     *
+     * @var   integer
+     * @since 4.0.0
+     */
+    private $accumulatedMemory = 0;
+
+    /**
+     * Constructor.
+     *
+     * @param   Registry      $params        Parameters.
+     * @param   DebugMonitor  $queryMonitor  Query monitor.
+     * @param   array         $profiles      Profile data.
+     * @param   array         $explains      Explain data
+     *
+     * @since 4.0.0
+     */
+    public function __construct(Registry $params, DebugMonitor $queryMonitor, array $profiles, array $explains)
+    {
+        $this->queryMonitor = $queryMonitor;
+
+        parent::__construct($params);
+
+        $this->profiles = $profiles;
+        $this->explains = $explains;
+    }
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.0.0
+     *
+     * @return array Collected data
+     */
+    public function collect(): array
+    {
+        $statements = $this->getStatements();
+
+        return [
+            'data' => [
+                'statements'               => $statements,
+                'nb_statements'            => \count($statements),
+                'accumulated_duration_str' => $this->getDataFormatter()->formatDuration($this->accumulatedDuration),
+                'memory_usage_str'         => $this->getDataFormatter()->formatBytes($this->accumulatedMemory),
+                'xdebug_link'              => $this->getXdebugLinkTemplate(),
+                'root_path'                => JPATH_ROOT,
+            ],
+            'count' => \count($this->queryMonitor->getLogs()),
+        ];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     *
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getWidgets(): array
+    {
+        return [
+            'queries' => [
+                'icon'    => 'database',
+                'widget'  => 'PhpDebugBar.Widgets.SQLQueriesWidget',
+                'map'     => $this->name . '.data',
+                'default' => '[]',
+            ],
+            'queries:badge' => [
+                'map'     => $this->name . '.count',
+                'default' => 'null',
+            ],
+        ];
+    }
+
+    /**
+     * Assets for the collector.
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getAssets(): array
+    {
+        return [
+            'css' => Uri::root(true) . '/media/plg_system_debug/widgets/sqlqueries/widget.min.css',
+            'js'  => Uri::root(true) . '/media/plg_system_debug/widgets/sqlqueries/widget.min.js',
+        ];
+    }
+
+    /**
+     * Prepare the executed statements data.
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    private function getStatements(): array
+    {
+        $statements    = [];
+        $logs          = $this->queryMonitor->getLogs();
+        $boundParams   = $this->queryMonitor->getBoundParams();
+        $timings       = $this->queryMonitor->getTimings();
+        $memoryLogs    = $this->queryMonitor->getMemoryLogs();
+        $stacks        = $this->queryMonitor->getCallStacks();
+        $collectStacks = $this->params->get('query_traces');
+
+        foreach ($logs as $id => $item) {
+            $queryTime   = 0;
+            $queryMemory = 0;
+
+            if ($timings && isset($timings[$id * 2 + 1])) {
+                // Compute the query time.
+                $queryTime                 = ($timings[$id * 2 + 1] - $timings[$id * 2]);
+                $this->accumulatedDuration += $queryTime;
+            }
+
+            if ($memoryLogs && isset($memoryLogs[$id * 2 + 1])) {
+                // Compute the query memory usage.
+                $queryMemory             = ($memoryLogs[$id * 2 + 1] - $memoryLogs[$id * 2]);
+                $this->accumulatedMemory += $queryMemory;
+            }
+
+            $trace          = [];
+            $callerLocation = '';
+
+            if (isset($stacks[$id])) {
+                $cnt = 0;
+
+                foreach ($stacks[$id] as $i => $stack) {
+                    $class = $stack['class'] ?? '';
+                    $file  = $stack['file'] ?? '';
+                    $line  = $stack['line'] ?? '';
+
+                    $caller   = $this->formatCallerInfo($stack);
+                    $location = $file && $line ? "$file:$line" : 'same';
+
+                    $isCaller = 0;
+
+                    if (\Joomla\Database\DatabaseDriver::class === $class && false === strpos($file, 'DatabaseDriver.php')) {
+                        $callerLocation = $location;
+                        $isCaller       = 1;
+                    }
+
+                    if ($collectStacks) {
+                        $trace[] = [\count($stacks[$id]) - $cnt, $isCaller, $caller, $file, $line];
+                    }
+
+                    $cnt++;
+                }
+            }
+
+            $explain        = $this->explains[$id] ?? [];
+            $explainColumns = [];
+
+            // Extract column labels for Explain table
+            if ($explain) {
+                $explainColumns = array_keys(reset($explain));
+            }
+
+            $statements[] = [
+                'sql'          => $item,
+                'params'       => $boundParams[$id] ?? [],
+                'duration_str' => $this->getDataFormatter()->formatDuration($queryTime),
+                'memory_str'   => $this->getDataFormatter()->formatBytes($queryMemory),
+                'caller'       => $callerLocation,
+                'callstack'    => $trace,
+                'explain'      => $explain,
+                'explain_col'  => $explainColumns,
+                'profile'      => $this->profiles[$id] ?? [],
+            ];
+        }
+
+        return $statements;
+    }
+}

plugins/system/debug/src/DataCollector/RequestDataCollector.php

@@ -0,0 +1,67 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use Joomla\Plugin\System\Debug\Extension\Debug;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Collects info about the request content while redacting potentially secret content
+ *
+ * @since  4.2.4
+ */
+class RequestDataCollector extends \DebugBar\DataCollector\RequestDataCollector
+{
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.2.4
+     *
+     * @return array
+     */
+    public function collect()
+    {
+        $vars       = ['_GET', '_POST', '_SESSION', '_COOKIE', '_SERVER'];
+        $returnData = [];
+
+        foreach ($vars as $var) {
+            if (isset($GLOBALS[$var])) {
+                $key = "$" . $var;
+
+                $data = $GLOBALS[$var];
+
+                // Replace Joomla session data from session data, it will be collected by SessionCollector
+                if ($var === '_SESSION' && !empty($data['joomla'])) {
+                    $data['joomla'] = '***redacted***';
+                }
+
+                array_walk_recursive($data, static function (&$value, $key) {
+                    if (!preg_match(Debug::PROTECTED_COLLECTOR_KEYS, $key)) {
+                        return;
+                    }
+
+                    $value = '***redacted***';
+                });
+
+                if ($this->isHtmlVarDumperUsed()) {
+                    $returnData[$key] = $this->getVarDumper()->renderVar($data);
+                } else {
+                    $returnData[$key] = $this->getDataFormatter()->formatVar($data);
+                }
+            }
+        }
+
+        return $returnData;
+    }
+}

plugins/system/debug/src/DataCollector/SessionCollector.php

@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use Joomla\CMS\Factory;
+use Joomla\Plugin\System\Debug\AbstractDataCollector;
+use Joomla\Plugin\System\Debug\Extension\Debug;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * SessionDataCollector
+ *
+ * @since  4.0.0
+ */
+class SessionCollector extends AbstractDataCollector
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.0.0
+     */
+    private $name = 'session';
+
+    /**
+     * Collected data.
+     *
+     * @var   array
+     * @since 4.4.0
+     */
+    protected $sessionData;
+
+    /**
+     * Constructor.
+     *
+     * @param   Registry  $params   Parameters.
+     * @param   bool      $collect  Collect the session data.
+     *
+     * @since 4.4.0
+     */
+    public function __construct($params, $collect = false)
+    {
+        parent::__construct($params);
+
+        if ($collect) {
+            $this->collect();
+        }
+    }
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @param   bool  $overwrite  Overwrite the previously collected session data.
+     *
+     * @return array Collected data
+     *
+     * @since  4.0.0
+     */
+    public function collect($overwrite = false)
+    {
+        if ($this->sessionData === null || $overwrite) {
+            $this->sessionData  = [];
+            $data               = Factory::getApplication()->getSession()->all();
+
+            // redact value of potentially secret keys
+            array_walk_recursive($data, static function (&$value, $key) {
+                if (!preg_match(Debug::PROTECTED_COLLECTOR_KEYS, $key)) {
+                    return;
+                }
+
+                $value = '***redacted***';
+            });
+
+            foreach ($data as $key => $value) {
+                $this->sessionData[$key] = $this->getDataFormatter()->formatVar($value);
+            }
+        }
+
+        return ['data' => $this->sessionData];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.0.0
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * Returns a hash where keys are control names and their values
+     * an array of options as defined in {@see \DebugBar\JavascriptRenderer::addControl()}
+     *
+     * @since  4.0.0
+     *
+     * @return array
+     */
+    public function getWidgets()
+    {
+        return [
+            'session' => [
+                'icon'    => 'key',
+                'widget'  => 'PhpDebugBar.Widgets.VariableListWidget',
+                'map'     => $this->name . '.data',
+                'default' => '[]',
+            ],
+        ];
+    }
+}

plugins/system/debug/src/DataCollector/UserCollector.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\DataCollector;
+
+use DebugBar\DataCollector\DataCollectorInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\User\UserFactoryInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * User collector that stores the user id of the person making the request allowing us to filter on it after storage
+ *
+ * @since  4.2.4
+ */
+class UserCollector implements DataCollectorInterface
+{
+    /**
+     * Collector name.
+     *
+     * @var   string
+     * @since 4.2.4
+     */
+    private $name = 'juser';
+
+    /**
+     * Called by the DebugBar when data needs to be collected
+     *
+     * @since  4.2.4
+     *
+     * @return array Collected data
+     */
+    public function collect()
+    {
+        $user = Factory::getApplication()->getIdentity()
+            ?: Factory::getContainer()->get(UserFactoryInterface::class)->loadUserById(0);
+
+        return ['user_id' => $user->id];
+    }
+
+    /**
+     * Returns the unique name of the collector
+     *
+     * @since  4.2.4
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+}

plugins/system/debug/src/DataFormatter.php

@@ -0,0 +1,93 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug;
+
+use DebugBar\DataFormatter\DataFormatter as DebugBarDataFormatter;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * DataFormatter
+ *
+ * @since  4.0.0
+ */
+class DataFormatter extends DebugBarDataFormatter
+{
+    /**
+     * Strip the root path.
+     *
+     * @param   string  $path         The path.
+     * @param   string  $replacement  The replacement
+     *
+     * @return string
+     *
+     * @since 4.0.0
+     */
+    public function formatPath($path, $replacement = ''): string
+    {
+        return str_replace(JPATH_ROOT, $replacement, $path);
+    }
+
+    /**
+     * Format a string from back trace.
+     *
+     * @param   array  $call  The array to format
+     *
+     * @return string
+     *
+     * @since 4.0.0
+     */
+    public function formatCallerInfo(array $call): string
+    {
+        $string = '';
+
+        if (isset($call['class'])) {
+            // If entry has Class/Method print it.
+            $string .= htmlspecialchars($call['class'] . $call['type'] . $call['function']) . '()';
+        } elseif (isset($call['args'][0]) && \is_array($call['args'][0])) {
+            $string .= htmlspecialchars($call['function']) . ' (';
+
+            foreach ($call['args'][0] as $arg) {
+                // Check if the arguments can be used as string
+                if (\is_object($arg) && !method_exists($arg, '__toString')) {
+                    $arg = \get_class($arg);
+                }
+
+                // Keep only the size of array
+                if (\is_array($arg)) {
+                    $arg = 'Array(count=' . \count($arg) . ')';
+                }
+
+                $string .= htmlspecialchars($arg) . ', ';
+            }
+
+            $string = rtrim($string, ', ') . ')';
+        } elseif (isset($call['args'][0])) {
+            $string .= htmlspecialchars($call['function']) . '(';
+
+            if (is_scalar($call['args'][0])) {
+                $string .= $call['args'][0];
+            } elseif (\is_object($call['args'][0])) {
+                $string .= \get_class($call['args'][0]);
+            } else {
+                $string .= \gettype($call['args'][0]);
+            }
+            $string .= ')';
+        } else {
+            // It's a function.
+            $string .= htmlspecialchars($call['function']) . '()';
+        }
+
+        return $string;
+    }
+}

plugins/system/debug/src/Extension/Debug.php

@@ -0,0 +1,712 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.debug
+ *
+ * @copyright   (C) 2006 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\Extension;
+
+use DebugBar\DataCollector\MessagesCollector;
+use DebugBar\DebugBar;
+use DebugBar\OpenHandler;
+use Joomla\Application\ApplicationEvents;
+use Joomla\CMS\Application\CMSApplicationInterface;
+use Joomla\CMS\Document\HtmlDocument;
+use Joomla\CMS\Event\Plugin\AjaxEvent;
+use Joomla\CMS\Log\Log;
+use Joomla\CMS\Log\LogEntry;
+use Joomla\CMS\Log\Logger\InMemoryLogger;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Profiler\Profiler;
+use Joomla\CMS\Session\Session;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Database\DatabaseInterface;
+use Joomla\Database\Event\ConnectionEvent;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Event\Event;
+use Joomla\Event\Priority;
+use Joomla\Event\SubscriberInterface;
+use Joomla\Plugin\System\Debug\DataCollector\InfoCollector;
+use Joomla\Plugin\System\Debug\DataCollector\LanguageErrorsCollector;
+use Joomla\Plugin\System\Debug\DataCollector\LanguageFilesCollector;
+use Joomla\Plugin\System\Debug\DataCollector\LanguageStringsCollector;
+use Joomla\Plugin\System\Debug\DataCollector\MemoryCollector;
+use Joomla\Plugin\System\Debug\DataCollector\ProfileCollector;
+use Joomla\Plugin\System\Debug\DataCollector\QueryCollector;
+use Joomla\Plugin\System\Debug\DataCollector\RequestDataCollector;
+use Joomla\Plugin\System\Debug\DataCollector\SessionCollector;
+use Joomla\Plugin\System\Debug\DataCollector\UserCollector;
+use Joomla\Plugin\System\Debug\JavascriptRenderer;
+use Joomla\Plugin\System\Debug\JoomlaHttpDriver;
+use Joomla\Plugin\System\Debug\Storage\FileStorage;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! Debug plugin.
+ *
+ * @since  1.5
+ */
+final class Debug extends CMSPlugin implements SubscriberInterface
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * List of protected keys that will be redacted in multiple data collected
+     *
+     * @since  4.2.4
+     */
+    public const PROTECTED_COLLECTOR_KEYS = "/password|passwd|pwd|secret|token|server_auth|_pass|smtppass|otpKey|otep/i";
+
+    /**
+     * True if debug lang is on.
+     *
+     * @var    boolean
+     * @since  3.0
+     */
+    private $debugLang;
+
+    /**
+     * Holds log entries handled by the plugin.
+     *
+     * @var    LogEntry[]
+     * @since  3.1
+     */
+    private $logEntries = [];
+
+    /**
+     * Holds all SHOW PROFILE FOR QUERY n, indexed by n-1.
+     *
+     * @var    array
+     * @since  3.1.2
+     */
+    private $sqlShowProfileEach = [];
+
+    /**
+     * Holds all EXPLAIN EXTENDED for all queries.
+     *
+     * @var    array
+     * @since  3.1.2
+     */
+    private $explains = [];
+
+    /**
+     * @var DebugBar
+     * @since 4.0.0
+     */
+    private $debugBar;
+
+    /**
+     * The query monitor.
+     *
+     * @var    \Joomla\Database\Monitor\DebugMonitor
+     * @since  4.0.0
+     */
+    private $queryMonitor;
+
+    /**
+     * AJAX marker
+     *
+     * @var   bool
+     * @since 4.0.0
+     */
+    protected $isAjax = false;
+
+    /**
+     * Whether displaying a logs is enabled
+     *
+     * @var   bool
+     * @since 4.0.0
+     */
+    protected $showLogs = false;
+
+    /**
+     * The time spent in onAfterDisconnect()
+     *
+     * @var   float
+     * @since 4.4.0
+     */
+    protected $timeInOnAfterDisconnect = 0;
+
+    /**
+     * @return  array
+     *
+     * @since   4.1.3
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onBeforeCompileHead' => 'onBeforeCompileHead',
+            'onAjaxDebug'         => 'onAjaxDebug',
+            'onBeforeRespond'     => 'onBeforeRespond',
+            'onAfterRespond'      => [
+                'onAfterRespond',
+                Priority::MIN,
+            ],
+            ApplicationEvents::AFTER_RESPOND => [
+                'onAfterRespond',
+                Priority::MIN,
+            ],
+            'onAfterDisconnect' => 'onAfterDisconnect',
+        ];
+    }
+
+    /**
+     * @param   DispatcherInterface      $dispatcher  The object to observe -- event dispatcher.
+     * @param   array                    $config      An optional associative array of configuration settings.
+     * @param   CMSApplicationInterface  $app         The app
+     * @param   DatabaseInterface        $db          The db
+     *
+     * @since   1.5
+     */
+    public function __construct(DispatcherInterface $dispatcher, array $config, CMSApplicationInterface $app, DatabaseInterface $db)
+    {
+        parent::__construct($dispatcher, $config);
+
+        $this->setApplication($app);
+        $this->setDatabase($db);
+
+        $this->debugLang = $this->getApplication()->get('debug_lang');
+
+        // Skip the plugin if debug is off
+        if (!$this->debugLang && !$this->getApplication()->get('debug')) {
+            return;
+        }
+
+        $this->getApplication()->set('gzip', false);
+        ob_start();
+        ob_implicit_flush(false);
+
+        /** @var \Joomla\Database\Monitor\DebugMonitor */
+        $this->queryMonitor = $this->getDatabase()->getMonitor();
+
+        if (!$this->params->get('queries', 1)) {
+            // Remove the database driver monitor
+            $this->getDatabase()->setMonitor(null);
+        }
+
+        $this->debugBar = new DebugBar();
+
+        // Check whether we want to track the request history for future use.
+        if ($this->params->get('track_request_history', false)) {
+            $storagePath = JPATH_CACHE . '/plg_system_debug_' . $this->getApplication()->getName();
+            $this->debugBar->setStorage(new FileStorage($storagePath));
+        }
+
+        $this->debugBar->setHttpDriver(new JoomlaHttpDriver($this->getApplication()));
+
+        $this->isAjax = $this->getApplication()->getInput()->get('option') === 'com_ajax'
+            && $this->getApplication()->getInput()->get('plugin') === 'debug' && $this->getApplication()->getInput()->get('group') === 'system';
+
+        $this->showLogs = (bool) $this->params->get('logs', true);
+
+        // Log deprecated class aliases
+        if ($this->showLogs && $this->getApplication()->get('log_deprecated')) {
+            foreach (\JLoader::getDeprecatedAliases() as $deprecation) {
+                Log::add(
+                    sprintf(
+                        '%1$s has been aliased to %2$s and the former class name is deprecated. The alias will be removed in %3$s.',
+                        $deprecation['old'],
+                        $deprecation['new'],
+                        $deprecation['version']
+                    ),
+                    Log::WARNING,
+                    'deprecation-notes'
+                );
+            }
+        }
+    }
+
+    /**
+     * Add an assets for debugger.
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onBeforeCompileHead()
+    {
+        // Only if debugging or language debug is enabled.
+        if ((JDEBUG || $this->debugLang) && $this->isAuthorisedDisplayDebug() && $this->getApplication()->getDocument() instanceof HtmlDocument) {
+            // Use our own jQuery and fontawesome instead of the debug bar shipped version
+            $assetManager = $this->getApplication()->getDocument()->getWebAssetManager();
+            $assetManager->registerAndUseStyle(
+                'plg.system.debug',
+                'plg_system_debug/debug.css',
+                [],
+                [],
+                ['fontawesome']
+            );
+            $assetManager->registerAndUseScript(
+                'plg.system.debug',
+                'plg_system_debug/debug.min.js',
+                [],
+                ['defer' => true],
+                ['jquery']
+            );
+        }
+
+        // Disable asset media version if needed.
+        if (JDEBUG && (int) $this->params->get('refresh_assets', 1) === 0) {
+            $this->getApplication()->getDocument()->setMediaVersion('');
+        }
+    }
+
+    /**
+     * Show the debug info.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function onAfterRespond()
+    {
+        $endTime    = microtime(true) - $this->timeInOnAfterDisconnect;
+        $endMemory  = memory_get_peak_usage(false);
+
+        // Do not collect data if debugging or language debug is not enabled.
+        if ((!JDEBUG && !$this->debugLang) || $this->isAjax) {
+            return;
+        }
+
+        // User has to be authorised to see the debug information.
+        if (!$this->isAuthorisedDisplayDebug()) {
+            return;
+        }
+
+        // Load language.
+        $this->loadLanguage();
+
+        $this->debugBar->addCollector(new InfoCollector($this->params, $this->debugBar->getCurrentRequestId()));
+        $this->debugBar->addCollector(new UserCollector());
+
+        if (JDEBUG) {
+            if ($this->params->get('memory', 1)) {
+                $this->debugBar->addCollector(new MemoryCollector($this->params, $endMemory));
+            }
+
+            if ($this->params->get('request', 1)) {
+                $this->debugBar->addCollector(new RequestDataCollector());
+            }
+
+            if ($this->params->get('session', 1)) {
+                $this->debugBar->addCollector(new SessionCollector($this->params, true));
+            }
+
+            if ($this->params->get('profile', 1)) {
+                $this->debugBar->addCollector((new ProfileCollector($this->params))->setRequestEndTime($endTime));
+            }
+
+            if ($this->params->get('queries', 1)) {
+                // Remember session form token for possible future usage.
+                $formToken = Session::getFormToken();
+
+                // Close session to collect possible session-related queries.
+                $this->getApplication()->getSession()->close();
+
+                // Call $db->disconnect() here to trigger the onAfterDisconnect() method here in this class!
+                $this->getDatabase()->disconnect();
+                $this->debugBar->addCollector(new QueryCollector($this->params, $this->queryMonitor, $this->sqlShowProfileEach, $this->explains));
+            }
+
+            if ($this->showLogs) {
+                $this->collectLogs();
+            }
+        }
+
+        if ($this->debugLang) {
+            $this->debugBar->addCollector(new LanguageFilesCollector($this->params));
+            $this->debugBar->addCollector(new LanguageStringsCollector($this->params));
+            $this->debugBar->addCollector(new LanguageErrorsCollector($this->params));
+        }
+
+        // Only render for HTML output.
+        if (!($this->getApplication()->getDocument() instanceof HtmlDocument)) {
+            $this->debugBar->stackData();
+
+            return;
+        }
+
+        $debugBarRenderer = new JavascriptRenderer($this->debugBar, Uri::root(true) . '/media/vendor/debugbar/');
+        $openHandlerUrl   = Uri::base(true) . '/index.php?option=com_ajax&plugin=debug&group=system&format=raw&action=openhandler';
+        $openHandlerUrl .= '&' . ($formToken ?? Session::getFormToken()) . '=1';
+
+        $debugBarRenderer->setOpenHandlerUrl($openHandlerUrl);
+
+        /**
+         * @todo disable highlightjs from the DebugBar, import it through NPM
+         *       and deliver it through Joomla's API
+         *       Also every DebugBar script and stylesheet needs to use Joomla's API
+         *       $debugBarRenderer->disableVendor('highlightjs');
+         */
+
+        // Capture output.
+        $contents = ob_get_contents();
+
+        if ($contents) {
+            ob_end_clean();
+        }
+
+        // No debug for Safari and Chrome redirection.
+        if (
+            strpos($contents, '<html><head><meta http-equiv="refresh" content="0;') === 0
+            && strpos(strtolower($_SERVER['HTTP_USER_AGENT'] ?? ''), 'webkit') !== false
+        ) {
+            $this->debugBar->stackData();
+
+            echo $contents;
+
+            return;
+        }
+
+        echo str_replace('</body>', $debugBarRenderer->renderHead() . $debugBarRenderer->render() . '</body>', $contents);
+    }
+
+    /**
+     * AJAX handler
+     *
+     * @param AjaxEvent $event
+     *
+     * @return  void
+     *
+     * @since  4.0.0
+     */
+    public function onAjaxDebug(AjaxEvent $event)
+    {
+        // Do not render if debugging or language debug is not enabled.
+        if (!JDEBUG && !$this->debugLang) {
+            return;
+        }
+
+        // User has to be authorised to see the debug information.
+        if (!$this->isAuthorisedDisplayDebug() || !Session::checkToken('request')) {
+            return;
+        }
+
+        switch ($this->getApplication()->getInput()->get('action')) {
+            case 'openhandler':
+                $handler = new OpenHandler($this->debugBar);
+                $result  = $handler->handle($this->getApplication()->getInput()->request->getArray(), false, false);
+
+                $event->addResult($result);
+        }
+    }
+
+    /**
+     * Method to check if the current user is allowed to see the debug information or not.
+     *
+     * @return  boolean  True if access is allowed.
+     *
+     * @since   3.0
+     */
+    private function isAuthorisedDisplayDebug(): bool
+    {
+        static $result;
+
+        if ($result !== null) {
+            return $result;
+        }
+
+        // If the user is not allowed to view the output then end here.
+        $filterGroups = (array) $this->params->get('filter_groups', []);
+
+        if (!empty($filterGroups)) {
+            $userGroups = $this->getApplication()->getIdentity()->get('groups');
+
+            if (!array_intersect($filterGroups, $userGroups)) {
+                $result = false;
+
+                return false;
+            }
+        }
+
+        $result = true;
+
+        return true;
+    }
+
+    /**
+     * Disconnect handler for database to collect profiling and explain information.
+     *
+     * @param   ConnectionEvent  $event  Event object
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onAfterDisconnect(ConnectionEvent $event)
+    {
+        if (!JDEBUG) {
+            return;
+        }
+
+        $startTime = microtime(true);
+
+        $db = $event->getDriver();
+
+        // Remove the monitor to avoid monitoring the following queries
+        $db->setMonitor(null);
+
+        if ($this->params->get('query_profiles') && $db->getServerType() === 'mysql') {
+            try {
+                // Check if profiling is enabled.
+                $db->setQuery("SHOW VARIABLES LIKE 'have_profiling'");
+                $hasProfiling = $db->loadResult();
+
+                if ($hasProfiling) {
+                    // Run a SHOW PROFILE query.
+                    $db->setQuery('SHOW PROFILES');
+                    $sqlShowProfiles = $db->loadAssocList();
+
+                    if ($sqlShowProfiles) {
+                        foreach ($sqlShowProfiles as $qn) {
+                            // Run SHOW PROFILE FOR QUERY for each query where a profile is available (max 100).
+                            $db->setQuery('SHOW PROFILE FOR QUERY ' . (int) $qn['Query_ID']);
+                            $this->sqlShowProfileEach[$qn['Query_ID'] - 1] = $db->loadAssocList();
+                        }
+                    }
+                } else {
+                    $this->sqlShowProfileEach[0] = [['Error' => 'MySql have_profiling = off']];
+                }
+            } catch (\Exception $e) {
+                $this->sqlShowProfileEach[0] = [['Error' => $e->getMessage()]];
+            }
+        }
+
+        if ($this->params->get('query_explains') && \in_array($db->getServerType(), ['mysql', 'postgresql'], true)) {
+            $logs        = $this->queryMonitor->getLogs();
+            $boundParams = $this->queryMonitor->getBoundParams();
+
+            foreach ($logs as $k => $query) {
+                $dbVersion56 = $db->getServerType() === 'mysql' && version_compare($db->getVersion(), '5.6', '>=');
+                $dbVersion80 = $db->getServerType() === 'mysql' && version_compare($db->getVersion(), '8.0', '>=');
+
+                if ($dbVersion80) {
+                    $dbVersion56 = false;
+                }
+
+                if ((stripos($query, 'select') === 0) || ($dbVersion56 && ((stripos($query, 'delete') === 0) || (stripos($query, 'update') === 0)))) {
+                    try {
+                        $queryInstance = $db->getQuery(true);
+                        $queryInstance->setQuery('EXPLAIN ' . ($dbVersion56 ? 'EXTENDED ' : '') . $query);
+
+                        if ($boundParams[$k]) {
+                            foreach ($boundParams[$k] as $key => $obj) {
+                                $queryInstance->bind($key, $obj->value, $obj->dataType, $obj->length, $obj->driverOptions);
+                            }
+                        }
+
+                        $this->explains[$k] = $db->setQuery($queryInstance)->loadAssocList();
+                    } catch (\Exception $e) {
+                        $this->explains[$k] = [['error' => $e->getMessage()]];
+                    }
+                }
+            }
+        }
+
+        $this->timeInOnAfterDisconnect = microtime(true) - $startTime;
+    }
+
+    /**
+     * Store log messages so they can be displayed later.
+     * This function is passed log entries by JLogLoggerCallback.
+     *
+     * @param   LogEntry  $entry  A log entry.
+     *
+     * @return  void
+     *
+     * @since   3.1
+     *
+     * @deprecated  4.3 will be removed in 6.0
+     *              Use \Joomla\CMS\Log\Log::add(LogEntry $entry) instead
+     */
+    public function logger(LogEntry $entry)
+    {
+        if (!$this->showLogs) {
+            return;
+        }
+
+        $this->logEntries[] = $entry;
+    }
+
+    /**
+     * Collect log messages.
+     *
+     * @return void
+     *
+     * @since 4.0.0
+     */
+    private function collectLogs()
+    {
+        $loggerOptions = ['group' => 'default'];
+        $logger        = new InMemoryLogger($loggerOptions);
+        $logEntries    = $logger->getCollectedEntries();
+
+        if (!$this->logEntries && !$logEntries) {
+            return;
+        }
+
+        if ($this->logEntries) {
+            $logEntries = array_merge($logEntries, $this->logEntries);
+        }
+
+        $logDeprecated     = $this->getApplication()->get('log_deprecated', 0);
+        $logDeprecatedCore = $this->params->get('log-deprecated-core', 0);
+
+        $this->debugBar->addCollector(new MessagesCollector('log'));
+
+        if ($logDeprecated) {
+            $this->debugBar->addCollector(new MessagesCollector('deprecated'));
+            $this->debugBar->addCollector(new MessagesCollector('deprecation-notes'));
+        }
+
+        if ($logDeprecatedCore) {
+            $this->debugBar->addCollector(new MessagesCollector('deprecated-core'));
+        }
+
+        foreach ($logEntries as $entry) {
+            switch ($entry->category) {
+                case 'deprecation-notes':
+                    if ($logDeprecated) {
+                        $this->debugBar[$entry->category]->addMessage($entry->message);
+                    }
+                    break;
+
+                case 'deprecated':
+                    if (!$logDeprecated && !$logDeprecatedCore) {
+                        break;
+                    }
+
+                    $file = '';
+                    $line = '';
+
+                    // Find the caller, skip Log methods and trigger_error function
+                    foreach ($entry->callStack as $stackEntry) {
+                        if (
+                            !empty($stackEntry['class'])
+                            && ($stackEntry['class'] === 'Joomla\CMS\Log\LogEntry' || $stackEntry['class'] === 'Joomla\CMS\Log\Log')
+                        ) {
+                            continue;
+                        }
+
+                        if (
+                            empty($stackEntry['class']) && !empty($stackEntry['function'])
+                            && $stackEntry['function'] === 'trigger_error'
+                        ) {
+                            continue;
+                        }
+
+                        $file = $stackEntry['file'] ?? '';
+                        $line = $stackEntry['line'] ?? '';
+
+                        break;
+                    }
+
+                    $category = $entry->category;
+                    $relative = $file ? str_replace(JPATH_ROOT, '', $file) : '';
+
+                    if ($relative && 0 === strpos($relative, '/libraries/src')) {
+                        if (!$logDeprecatedCore) {
+                            break;
+                        }
+
+                        $category .= '-core';
+                    } elseif (!$logDeprecated) {
+                        break;
+                    }
+
+                    $message = [
+                        'message' => $entry->message,
+                        'caller'  => $file . ':' . $line,
+                        // @todo 'stack' => $entry->callStack;
+                    ];
+                    $this->debugBar[$category]->addMessage($message, 'warning');
+                    break;
+
+                case 'databasequery':
+                    // Should be collected by its own collector
+                    break;
+
+                default:
+                    switch ($entry->priority) {
+                        case Log::EMERGENCY:
+                        case Log::ALERT:
+                        case Log::CRITICAL:
+                        case Log::ERROR:
+                            $level = 'error';
+                            break;
+                        case Log::WARNING:
+                            $level = 'warning';
+                            break;
+                        default:
+                            $level = 'info';
+                    }
+
+                    $this->debugBar['log']->addMessage($entry->category . ' - ' . $entry->message, $level);
+                    break;
+            }
+        }
+    }
+
+    /**
+     * Add server timing headers when profile is activated.
+     *
+     * @return  void
+     *
+     * @since   4.1.0
+     */
+    public function onBeforeRespond(): void
+    {
+        if (!JDEBUG || !$this->params->get('profile', 1)) {
+            return;
+        }
+
+        $metrics    = '';
+        $moduleTime = 0;
+        $accessTime = 0;
+
+        foreach (Profiler::getInstance('Application')->getMarks() as $index => $mark) {
+            // Ignore the before mark as the after one contains the timing of the action
+            if (stripos($mark->label, 'before') !== false) {
+                continue;
+            }
+
+            // Collect the module render time
+            if (strpos($mark->label, 'mod_') !== false) {
+                $moduleTime += $mark->time;
+                continue;
+            }
+
+            // Collect the access render time
+            if (strpos($mark->label, 'Access:') !== false) {
+                $accessTime += $mark->time;
+                continue;
+            }
+
+            $desc     = str_ireplace('after', '', $mark->label);
+            $name     = preg_replace('/[^\da-z]/i', '', $desc);
+            $metrics .= sprintf('%s;dur=%f;desc="%s", ', $index . $name, $mark->time, $desc);
+
+            // Do not create too large headers, some web servers don't love them
+            if (\strlen($metrics) > 3000) {
+                $metrics .= 'System;dur=0;desc="Data truncated to 3000 characters", ';
+                break;
+            }
+        }
+
+        // Add the module entry
+        $metrics .= 'Modules;dur=' . $moduleTime . ';desc="Modules", ';
+
+        // Add the access entry
+        $metrics .= 'Access;dur=' . $accessTime . ';desc="Access"';
+
+        $this->getApplication()->setHeader('Server-Timing', $metrics);
+    }
+}

plugins/system/debug/src/JavascriptRenderer.php

@@ -0,0 +1,133 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2019 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug;
+
+use DebugBar\DebugBar;
+use DebugBar\JavascriptRenderer as DebugBarJavascriptRenderer;
+use Joomla\CMS\Factory;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Custom JavascriptRenderer for DebugBar
+ *
+ * @since  4.0.0
+ */
+class JavascriptRenderer extends DebugBarJavascriptRenderer
+{
+    /**
+     * Class constructor.
+     *
+     * @param   \DebugBar\DebugBar  $debugBar  DebugBar instance
+     * @param   string              $baseUrl   The base URL from which assets will be served
+     * @param   string              $basePath  The path which assets are relative to
+     *
+     * @since  4.0.0
+     */
+    public function __construct(DebugBar $debugBar, $baseUrl = null, $basePath = null)
+    {
+        parent::__construct($debugBar, $baseUrl, $basePath);
+
+        // Disable features that loaded by Joomla! API, or not in use
+        $this->setEnableJqueryNoConflict(false);
+        $this->disableVendor('jquery');
+        $this->disableVendor('fontawesome');
+    }
+
+    /**
+     * Renders the html to include needed assets
+     *
+     * Only useful if Assetic is not used
+     *
+     * @return string
+     *
+     * @since  4.0.0
+     */
+    public function renderHead()
+    {
+        list($cssFiles, $jsFiles, $inlineCss, $inlineJs, $inlineHead) = $this->getAssets(null, self::RELATIVE_URL);
+        $html                                                         = '';
+        $doc                                                          = Factory::getApplication()->getDocument();
+
+        foreach ($cssFiles as $file) {
+            $html .= sprintf('<link rel="stylesheet" type="text/css" href="%s">' . "\n", $file);
+        }
+
+        foreach ($inlineCss as $content) {
+            $html .= sprintf('<style>%s</style>' . "\n", $content);
+        }
+
+        foreach ($jsFiles as $file) {
+            $html .= sprintf('<script type="text/javascript" src="%s" defer></script>' . "\n", $file);
+        }
+
+        $nonce = '';
+
+        if ($doc->cspNonce) {
+            $nonce = ' nonce="' . $doc->cspNonce . '"';
+        }
+
+        foreach ($inlineJs as $content) {
+            $html .= sprintf('<script type="module"%s>%s</script>' . "\n", $nonce, $content);
+        }
+
+        foreach ($inlineHead as $content) {
+            $html .= $content . "\n";
+        }
+
+        return $html;
+    }
+
+    /**
+     * Returns the code needed to display the debug bar
+     *
+     * AJAX request should not render the initialization code.
+     *
+     * @param   boolean  $initialize         Whether or not to render the debug bar initialization code
+     * @param   boolean  $renderStackedData  Whether or not to render the stacked data
+     *
+     * @return string
+     *
+     * @since  4.0.0
+     */
+    public function render($initialize = true, $renderStackedData = true)
+    {
+        $js  = '';
+        $doc = Factory::getApplication()->getDocument();
+
+        if ($initialize) {
+            $js = $this->getJsInitializationCode();
+        }
+
+        if ($renderStackedData && $this->debugBar->hasStackedData()) {
+            foreach ($this->debugBar->getStackedData() as $id => $data) {
+                $js .= $this->getAddDatasetCode($id, $data, '(stacked)');
+            }
+        }
+
+        $suffix = !$initialize ? '(ajax)' : null;
+        $js .= $this->getAddDatasetCode($this->debugBar->getCurrentRequestId(), $this->debugBar->getData(), $suffix);
+
+        $nonce = '';
+
+        if ($doc->cspNonce) {
+            $nonce = ' nonce="' . $doc->cspNonce . '"';
+        }
+
+        if ($this->useRequireJs) {
+            return "<script type=\"module\"$nonce>\nrequire(['debugbar'], function(PhpDebugBar){ $js });\n</script>\n";
+        }
+
+        return "<script type=\"module\"$nonce>\n$js\n</script>\n";
+    }
+}

plugins/system/debug/src/JoomlaHttpDriver.php

@@ -0,0 +1,134 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug;
+
+use DebugBar\HttpDriverInterface;
+use Joomla\Application\WebApplicationInterface;
+use Joomla\CMS\Application\CMSApplicationInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla HTTP driver for DebugBar
+ *
+ * @since   4.1.5
+ */
+final class JoomlaHttpDriver implements HttpDriverInterface
+{
+    /**
+     * @var CMSApplicationInterface
+     *
+     * @since   4.1.5
+     */
+    private $app;
+
+    /**
+     * @var array
+     *
+     * @since   4.1.5
+     */
+    private $dummySession = [];
+
+    /**
+     * Constructor.
+     *
+     * @param   CMSApplicationInterface  $app
+     *
+     * @since   4.1.5
+     */
+    public function __construct(CMSApplicationInterface $app)
+    {
+        $this->app = $app;
+    }
+
+    /**
+     * Sets HTTP headers
+     *
+     * @param   array  $headers
+     *
+     * @since   4.1.5
+     */
+    public function setHeaders(array $headers)
+    {
+        if ($this->app instanceof WebApplicationInterface) {
+            foreach ($headers as $name => $value) {
+                $this->app->setHeader($name, $value, true);
+            }
+        }
+    }
+
+    /**
+     * Checks if the session is started
+     *
+     * @return  boolean
+     *
+     * @since   4.1.5
+     */
+    public function isSessionStarted()
+    {
+        return true;
+    }
+
+    /**
+     * Sets a value in the session
+     *
+     * @param   string  $name
+     * @param   string  $value
+     *
+     * @since   4.1.5
+     */
+    public function setSessionValue($name, $value)
+    {
+        $this->dummySession[$name] = $value;
+    }
+
+    /**
+     * Checks if a value is in the session
+     *
+     * @param   string  $name
+     *
+     * @return  boolean
+     *
+     * @since   4.1.5
+     */
+    public function hasSessionValue($name)
+    {
+        return \array_key_exists($name, $this->dummySession);
+    }
+
+    /**
+     * Returns a value from the session
+     *
+     * @param   string  $name
+     *
+     * @return  mixed
+     *
+     * @since   4.1.5
+     */
+    public function getSessionValue($name)
+    {
+        return $this->dummySession[$name] ?? null;
+    }
+
+    /**
+     * Deletes a value from the session
+     *
+     * @param string $name
+     *
+     * @since   4.1.5
+     */
+    public function deleteSessionValue($name)
+    {
+        unset($this->dummySession[$name]);
+    }
+}

plugins/system/debug/src/Storage/FileStorage.php

@@ -0,0 +1,192 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.Debug
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Debug\Storage;
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\Filesystem\Folder;
+use Joomla\CMS\User\UserFactoryInterface;
+use Joomla\Filesystem\File;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Stores collected data into files
+ *
+ * @since  4.0.0
+ */
+class FileStorage extends \DebugBar\Storage\FileStorage
+{
+    /**
+     * Saves collected data
+     *
+     * @param   string  $id    The log id
+     * @param   string  $data  The log data
+     *
+     * @return  void
+     *
+     * @since  4.0.0
+     */
+    public function save($id, $data)
+    {
+        if (!file_exists($this->dirname)) {
+            Folder::create($this->dirname);
+        }
+
+        $dataStr = '<?php die(); ?>#(^-^)#' . json_encode($data);
+
+        File::write($this->makeFilename($id), $dataStr);
+    }
+
+    /**
+     * Returns collected data with the specified id
+     *
+     * @param   string  $id  The log id
+     *
+     * @return  array
+     *
+     * @since  4.0.0
+     */
+    public function get($id)
+    {
+        $dataStr = file_get_contents($this->makeFilename($id));
+        $dataStr = str_replace('<?php die(); ?>#(^-^)#', '', $dataStr);
+
+        return json_decode($dataStr, true) ?: [];
+    }
+
+    /**
+     * Returns a metadata about collected data
+     *
+     * @param   array    $filters  Filtering options
+     * @param   integer  $max      The limit, items per page
+     * @param   integer  $offset   The offset
+     *
+     * @return  array
+     *
+     * @since 4.0.0
+     */
+    public function find(array $filters = [], $max = 20, $offset = 0)
+    {
+        // Loop through all .php files and remember the modified time and id.
+        $files = [];
+
+        foreach (new \DirectoryIterator($this->dirname) as $file) {
+            if ($file->getExtension() == 'php') {
+                $files[] = [
+                    'time' => $file->getMTime(),
+                    'id'   => $file->getBasename('.php'),
+                ];
+            }
+        }
+
+        // Sort the files, newest first
+        usort(
+            $files,
+            function ($a, $b) {
+                if ($a['time'] === $b['time']) {
+                    return 0;
+                }
+
+                return $a['time'] < $b['time'] ? 1 : -1;
+            }
+        );
+
+        // Load the metadata and filter the results.
+        $results = [];
+        $i       = 0;
+
+        foreach ($files as $file) {
+            // When filter is empty, skip loading the offset
+            if ($i++ < $offset && empty($filters)) {
+                $results[] = null;
+                continue;
+            }
+
+            $data = $this->get($file['id']);
+
+            if (!$this->isSecureToReturnData($data)) {
+                continue;
+            }
+
+            $meta = $data['__meta'];
+            unset($data);
+
+            if ($this->filter($meta, $filters)) {
+                $results[] = $meta;
+            }
+
+            if (\count($results) >= ($max + $offset)) {
+                break;
+            }
+        }
+
+        return \array_slice($results, $offset, $max);
+    }
+
+    /**
+     * Get a full path to the file
+     *
+     * @param   string  $id  The log id
+     *
+     * @return string
+     *
+     * @since 4.0.0
+     */
+    public function makeFilename($id)
+    {
+        return $this->dirname . basename($id) . '.php';
+    }
+
+    /**
+     * Check if the user is allowed to view the request. Users can only see their own requests.
+     *
+     * @param   array  $data  The data item to process
+     *
+     * @return boolean
+     *
+     * @since 4.2.4
+     */
+    private function isSecureToReturnData($data): bool
+    {
+        /**
+         * We only started this collector in Joomla 4.2.4 - any older files we have to assume are insecure.
+         */
+        if (!\array_key_exists('juser', $data)) {
+            return false;
+        }
+
+        $currentUser           = Factory::getUser();
+        $currentUserId         = $currentUser->id;
+        $currentUserSuperAdmin = $currentUser->authorise('core.admin');
+
+        /**
+         * Guests aren't allowed to look at other requests because there's no guarantee it's the same guest. Potentially
+         * in the future this could be refined to check the session ID to show some requests. But it's unlikely we want
+         * guests to be using the debug bar anyhow
+         */
+        if ($currentUserId === 0) {
+            return false;
+        }
+
+        /** @var \Joomla\CMS\User\User $user */
+        $user = Factory::getContainer()->get(UserFactoryInterface::class)
+            ->loadUserById($data['juser']['user_id']);
+
+        // Super users are allowed to look at other users requests. Otherwise users can only see their own requests.
+        if ($currentUserSuperAdmin || $user->id === $currentUserId) {
+            return true;
+        }
+
+        return false;
+    }
+}

plugins/system/fields/fields.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_fields</name>
+	<author>Joomla! Project</author>
+	<creationDate>2016-03</creationDate>
+	<copyright>(C) 2016 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.7.0</version>
+	<description>PLG_SYSTEM_FIELDS_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Fields</namespace>
+	<files>
+		<folder plugin="fields">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_fields.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_fields.sys.ini</language>
+	</languages>
+</extension>

plugins/system/fields/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.fields
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserFactoryInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Fields\Extension\Fields;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Fields(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'fields')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setUserFactory($container->get(UserFactoryInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/fields/src/Extension/Fields.php

@@ -0,0 +1,483 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.fields
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Fields\Extension;
+
+use Joomla\CMS\Event\Content;
+use Joomla\CMS\Event\Model;
+use Joomla\CMS\Language\Multilanguage;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\User\UserFactoryAwareTrait;
+use Joomla\Component\Fields\Administrator\Helper\FieldsHelper;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Fields Plugin
+ *
+ * @since  3.7
+ */
+final class Fields extends CMSPlugin
+{
+    use UserFactoryAwareTrait;
+
+    /**
+     * Normalizes the request data.
+     *
+     * @param   Model\NormaliseRequestDataEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.8.7
+     */
+    public function onContentNormaliseRequestData(Model\NormaliseRequestDataEvent $event)
+    {
+        $context = $event->getContext();
+        $data    = $event->getData();
+        $form    = $event->getForm();
+
+        if (!FieldsHelper::extract($context, $data)) {
+            return;
+        }
+
+        // Loop over all fields
+        foreach ($form->getGroup('com_fields') as $field) {
+            if ($field->disabled === true) {
+                /**
+                 * Disabled fields should NEVER be added to the request as
+                 * they should NEVER be added by the browser anyway so nothing to check against
+                 * as "disabled" means no interaction at all.
+                 */
+
+                // Make sure the data object has an entry before delete it
+                if (isset($data->com_fields[$field->fieldname])) {
+                    unset($data->com_fields[$field->fieldname]);
+                }
+
+                continue;
+            }
+
+            // Make sure the data object has an entry
+            if (isset($data->com_fields[$field->fieldname])) {
+                continue;
+            }
+
+            // Set a default value for the field
+            $data->com_fields[$field->fieldname] = false;
+        }
+    }
+
+    /**
+     * The save event.
+     *
+     * @param   string                   $context  The context
+     * @param   \Joomla\CMS\Table\Table  $item     The table
+     * @param   boolean                  $isNew    Is new item
+     * @param   array                    $data     The validated data
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentAfterSave($context, $item, $isNew, $data = []): void
+    {
+        // Check if data is an array and the item has an id
+        if (!\is_array($data) || empty($item->id) || empty($data['com_fields'])) {
+            return;
+        }
+
+        // Create correct context for category
+        if ($context === 'com_categories.category') {
+            $context = $item->extension . '.categories';
+
+            // Set the catid on the category to get only the fields which belong to this category
+            $item->catid = $item->id;
+        }
+
+        // Check the context
+        $parts = FieldsHelper::extract($context, $item);
+
+        if (!$parts) {
+            return;
+        }
+
+        // Compile the right context for the fields
+        $context = $parts[0] . '.' . $parts[1];
+
+        // Loading the fields
+        $fields = FieldsHelper::getFields($context, $item);
+
+        if (!$fields) {
+            return;
+        }
+
+        // Loading the model
+
+        /** @var \Joomla\Component\Fields\Administrator\Model\FieldModel $model */
+        $model = $this->getApplication()->bootComponent('com_fields')->getMVCFactory()
+            ->createModel('Field', 'Administrator', ['ignore_request' => true]);
+
+        // Loop over the fields
+        foreach ($fields as $field) {
+            // Determine the value if it is (un)available from the data
+            if (\array_key_exists($field->name, $data['com_fields'])) {
+                $value = $data['com_fields'][$field->name] === false ? null : $data['com_fields'][$field->name];
+            } else {
+                // Field not available on form, use stored value
+                $value = $field->rawvalue;
+            }
+
+            // If no value set (empty) remove value from database
+            if (\is_array($value) ? !\count($value) : !\strlen($value)) {
+                $value = null;
+            }
+
+            // JSON encode value for complex fields
+            if (\is_array($value) && (\count($value, COUNT_NORMAL) !== \count($value, COUNT_RECURSIVE) || !\count(array_filter(array_keys($value), 'is_numeric')))) {
+                $value = json_encode($value);
+            }
+
+            // Setting the value for the field and the item
+            $model->setFieldValue($field->id, $item->id, $value);
+        }
+    }
+
+    /**
+     * The save event.
+     *
+     * @param   array    $userData  The date
+     * @param   boolean  $isNew     Is new
+     * @param   boolean  $success   Is success
+     * @param   string   $msg       The message
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onUserAfterSave($userData, $isNew, $success, $msg): void
+    {
+        // It is not possible to manipulate the user during save events
+        // Check if data is valid or we are in a recursion
+        if (!$userData['id'] || !$success) {
+            return;
+        }
+
+        $user = $this->getUserFactory()->loadUserById($userData['id']);
+
+        $task = $this->getApplication()->getInput()->getCmd('task');
+
+        // Skip fields save when we activate a user, because we will lose the saved data
+        if (\in_array($task, ['activate', 'block', 'unblock'])) {
+            return;
+        }
+
+        // Trigger the events with a real user
+        $this->onContentAfterSave('com_users.user', $user, false, $userData);
+    }
+
+    /**
+     * The delete event.
+     *
+     * @param   string    $context  The context
+     * @param   \stdClass  $item     The item
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentAfterDelete($context, $item): void
+    {
+        // Set correct context for category
+        if ($context === 'com_categories.category') {
+            $context = $item->extension . '.categories';
+        }
+
+        $parts = FieldsHelper::extract($context, $item);
+
+        if (!$parts || empty($item->id)) {
+            return;
+        }
+
+        $context = $parts[0] . '.' . $parts[1];
+
+        /** @var \Joomla\Component\Fields\Administrator\Model\FieldModel $model */
+        $model = $this->getApplication()->bootComponent('com_fields')->getMVCFactory()
+            ->createModel('Field', 'Administrator', ['ignore_request' => true]);
+        $model->cleanupValues($context, $item->id);
+    }
+
+    /**
+     * The user delete event.
+     *
+     * @param   \stdClass  $user    The context
+     * @param   boolean   $success Is success
+     * @param   string    $msg     The message
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onUserAfterDelete($user, $success, $msg): void
+    {
+        $item     = new \stdClass();
+        $item->id = $user['id'];
+
+        $this->onContentAfterDelete('com_users.user', $item);
+    }
+
+    /**
+     * The form event.
+     *
+     * @param   Model\PrepareFormEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentPrepareForm(Model\PrepareFormEvent $event)
+    {
+        $form    = $event->getForm();
+        $data    = $event->getData();
+        $context = $form->getName();
+
+        // When a category is edited, the context is com_categories.categorycom_content
+        if (strpos($context, 'com_categories.category') === 0) {
+            $context = str_replace('com_categories.category', '', $context) . '.categories';
+            $data    = $data ?: $this->getApplication()->getInput()->get('jform', [], 'array');
+
+            // Set the catid on the category to get only the fields which belong to this category
+            if (\is_array($data) && \array_key_exists('id', $data)) {
+                $data['catid'] = $data['id'];
+            }
+
+            if (\is_object($data) && isset($data->id)) {
+                $data->catid = $data->id;
+            }
+        }
+
+        $parts = FieldsHelper::extract($context, $form);
+
+        if (!$parts) {
+            return;
+        }
+
+        $input = $this->getApplication()->getInput();
+
+        // If we are on the save command we need the actual data
+        $jformData = $input->get('jform', [], 'array');
+
+        if ($jformData && !$data) {
+            $data = $jformData;
+        }
+
+        if (\is_array($data)) {
+            $data = (object) $data;
+        }
+
+        FieldsHelper::prepareForm($parts[0] . '.' . $parts[1], $form, $data);
+    }
+
+    /**
+     * The display event.
+     *
+     * @param   Content\AfterTitleEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentAfterTitle(Content\AfterTitleEvent $event)
+    {
+        $event->addResult($this->display($event->getContext(), $event->getItem(), $event->getParams(), 1));
+    }
+
+    /**
+     * The display event.
+     *
+     * @param   Content\BeforeDisplayEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentBeforeDisplay(Content\BeforeDisplayEvent $event)
+    {
+        $event->addResult($this->display($event->getContext(), $event->getItem(), $event->getParams(), 2));
+    }
+
+    /**
+     * The display event.
+     *
+     * @param   Content\AfterDisplayEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentAfterDisplay(Content\AfterDisplayEvent $event)
+    {
+        $event->addResult($this->display($event->getContext(), $event->getItem(), $event->getParams(), 3));
+    }
+
+    /**
+     * Performs the display event.
+     *
+     * @param   string    $context      The context
+     * @param   \stdClass  $item         The item
+     * @param   Registry  $params       The params
+     * @param   integer   $displayType  The type
+     *
+     * @return  string
+     *
+     * @since   3.7.0
+     */
+    private function display($context, $item, $params, $displayType)
+    {
+        $parts = FieldsHelper::extract($context, $item);
+
+        if (!$parts) {
+            return '';
+        }
+
+        // If we have a category, set the catid field to fetch only the fields which belong to it
+        if ($parts[1] === 'categories' && !isset($item->catid)) {
+            $item->catid = $item->id;
+        }
+
+        $context = $parts[0] . '.' . $parts[1];
+
+        // Convert tags
+        if ($context == 'com_tags.tag' && !empty($item->type_alias)) {
+            // Set the context
+            $context = $item->type_alias;
+
+            $item = $this->prepareTagItem($item);
+        }
+
+        if (\is_string($params) || !$params) {
+            $params = new Registry($params);
+        }
+
+        $fields = FieldsHelper::getFields($context, $item, $displayType);
+
+        if ($fields) {
+            if ($this->getApplication()->isClient('site') && Multilanguage::isEnabled() && isset($item->language) && $item->language === '*') {
+                $lang = $this->getApplication()->getLanguage()->getTag();
+
+                foreach ($fields as $key => $field) {
+                    if ($field->language === '*' || $field->language == $lang) {
+                        continue;
+                    }
+
+                    unset($fields[$key]);
+                }
+            }
+        }
+
+        if ($fields) {
+            foreach ($fields as $key => $field) {
+                $fieldDisplayType = $field->params->get('display', '2');
+
+                if ($fieldDisplayType == $displayType) {
+                    continue;
+                }
+
+                unset($fields[$key]);
+            }
+        }
+
+        if ($fields) {
+            return FieldsHelper::render(
+                $context,
+                'fields.render',
+                [
+                    'item'    => $item,
+                    'context' => $context,
+                    'fields'  => $fields,
+                ]
+            );
+        }
+
+        return '';
+    }
+
+    /**
+     * Performs the display event.
+     *
+     * @param   Content\ContentPrepareEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.7.0
+     */
+    public function onContentPrepare(Content\ContentPrepareEvent $event)
+    {
+        $context = $event->getContext();
+        $item    = $event->getItem();
+
+        // Check property exists (avoid costly & useless recreation), if need to recreate them, just unset the property!
+        if (isset($item->jcfields)) {
+            return;
+        }
+
+        $parts = FieldsHelper::extract($context, $item);
+
+        if (!$parts) {
+            return;
+        }
+
+        $context = $parts[0] . '.' . $parts[1];
+
+        // Convert tags
+        if ($context == 'com_tags.tag' && !empty($item->type_alias)) {
+            // Set the context
+            $context = $item->type_alias;
+
+            $item = $this->prepareTagItem($item);
+        }
+
+        // Get item's fields, also preparing their value property for manual display
+        // (calling plugins events and loading layouts to get their HTML display)
+        $fields = FieldsHelper::getFields($context, $item, true);
+
+        // Adding the fields to the object
+        $item->jcfields = [];
+
+        foreach ($fields as $key => $field) {
+            $item->jcfields[$field->id] = $field;
+        }
+    }
+
+    /**
+     * Prepares a tag item to be ready for com_fields.
+     *
+     * @param   \stdClass  $item  The item
+     *
+     * @return  object
+     *
+     * @since   3.8.4
+     */
+    private function prepareTagItem($item)
+    {
+        // Map core fields
+        $item->id       = $item->content_item_id;
+        $item->language = $item->core_language;
+
+        // Also handle the catid
+        if (!empty($item->core_catid)) {
+            $item->catid = $item->core_catid;
+        }
+
+        return $item;
+    }
+}

plugins/system/guidedtours/guidedtours.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_guidedtours</name>
+	<author>Joomla! Project</author>
+	<creationDate>2023-02</creationDate>
+	<copyright>(C) 2023 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.3.0</version>
+	<description>PLG_SYSTEM_GUIDEDTOURS_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\GuidedTours</namespace>
+	<files>
+		<folder plugin="guidedtours">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_guidedtours.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_guidedtours.sys.ini</language>
+	</languages>
+</extension>

plugins/system/guidedtours/services/provider.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.guidedtours
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\WebAsset\WebAssetRegistry;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\GuidedTours\Extension\GuidedTours;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.3.0
+     */
+    public function register(Container $container)
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $app        = Factory::getApplication();
+
+                $plugin = new GuidedTours(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'guidedtours'),
+                    $app->isClient('administrator')
+                );
+
+                $plugin->setApplication($app);
+
+                $wa = $container->get(WebAssetRegistry::class);
+
+                $wa->addRegistryFile('media/plg_system_guidedtours/joomla.asset.json');
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/guidedtours/src/Extension/GuidedTours.php

@@ -0,0 +1,260 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.guidedtours
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\GuidedTours\Extension;
+
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Session\Session;
+use Joomla\Component\Guidedtours\Administrator\Extension\GuidedtoursComponent;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Event\Event;
+use Joomla\Event\SubscriberInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Guided Tours plugin to add interactive tours to the administrator interface.
+ *
+ * @since  4.3.0
+ */
+final class GuidedTours extends CMSPlugin implements SubscriberInterface
+{
+    /**
+     * A mapping for the step types
+     *
+     * @var    string[]
+     * @since  4.3.0
+     */
+    protected $stepType = [
+        GuidedtoursComponent::STEP_NEXT        => 'next',
+        GuidedtoursComponent::STEP_REDIRECT    => 'redirect',
+        GuidedtoursComponent::STEP_INTERACTIVE => 'interactive',
+    ];
+
+    /**
+     * A mapping for the step interactive types
+     *
+     * @var    string[]
+     * @since  4.3.0
+     */
+    protected $stepInteractiveType = [
+        GuidedtoursComponent::STEP_INTERACTIVETYPE_FORM_SUBMIT => 'submit',
+        GuidedtoursComponent::STEP_INTERACTIVETYPE_TEXT        => 'text',
+        GuidedtoursComponent::STEP_INTERACTIVETYPE_OTHER       => 'other',
+        GuidedtoursComponent::STEP_INTERACTIVETYPE_BUTTON      => 'button',
+    ];
+
+    /**
+     * An internal flag whether plugin should listen any event.
+     *
+     * @var bool
+     *
+     * @since   4.3.0
+     */
+    protected static $enabled = false;
+
+    /**
+     * Constructor
+     *
+     * @param   DispatcherInterface  $dispatcher  The object to observe
+     * @param   array                $config      An optional associative array of configuration settings.
+     * @param   boolean              $enabled     An internal flag whether plugin should listen any event.
+     *
+     * @since   4.3.0
+     */
+    public function __construct(DispatcherInterface $dispatcher, array $config = [], bool $enabled = false)
+    {
+        self::$enabled = $enabled;
+
+        parent::__construct($dispatcher, $config);
+    }
+
+    /**
+     * function for getSubscribedEvents : new Joomla 4 feature
+     *
+     * @return array
+     *
+     * @since   4.3.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return self::$enabled ? [
+            'onAjaxGuidedtours'   => 'startTour',
+            'onBeforeCompileHead' => 'onBeforeCompileHead',
+        ] : [];
+    }
+
+    /**
+     * Retrieve and starts a tour and its steps through Ajax.
+     *
+     * @return null|object
+     *
+     * @since   4.3.0
+     */
+    public function startTour(Event $event)
+    {
+        $tourId  = (int) $this->getApplication()->getInput()->getInt('id');
+        $tourUid = $this->getApplication()->getInput()->getString('uid', '');
+        $tourUid = $tourUid !== '' ? urldecode($tourUid) : '';
+
+        $tour = null;
+
+        // Load plugin language files
+        $this->loadLanguage();
+
+        if ($tourId > 0) {
+            $tour = $this->getTour($tourId);
+        } elseif ($tourUid !== '') {
+            $tour = $this->getTour($tourUid);
+        }
+
+        $event->setArgument('result', $tour ?? new \stdClass());
+
+        return $tour;
+    }
+
+    /**
+     * Listener for the `onBeforeCompileHead` event
+     *
+     * @return  void
+     *
+     * @since   4.3.0
+     */
+    public function onBeforeCompileHead()
+    {
+        $app  = $this->getApplication();
+        $doc  = $app->getDocument();
+        $user = $app->getIdentity();
+
+        if ($user != null && $user->id > 0) {
+            // Load plugin language files
+            $this->loadLanguage();
+
+            Text::script('JCANCEL');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_BACK');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_COMPLETE');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_COULD_NOT_LOAD_THE_TOUR');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_NEXT');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_START');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_STEP_NUMBER_OF');
+            Text::script('PLG_SYSTEM_GUIDEDTOURS_TOUR_ERROR');
+
+            $doc->addScriptOptions('com_guidedtours.token', Session::getFormToken());
+
+            // Load required assets
+            $doc->getWebAssetManager()
+                ->usePreset('plg_system_guidedtours.guidedtours');
+        }
+    }
+
+    /**
+     * Get a tour and its steps or null if not found
+     *
+     * @param   integer|string  $tourId  The ID or Uid of the tour to load
+     *
+     * @return null|object
+     *
+     * @since   4.3.0
+     */
+    private function getTour($tourId)
+    {
+        $app = $this->getApplication();
+
+        $factory = $app->bootComponent('com_guidedtours')->getMVCFactory();
+
+        $tourModel = $factory->createModel(
+            'Tour',
+            'Administrator',
+            ['ignore_request' => true]
+        );
+
+        $item = $tourModel->getItem($tourId);
+
+        return $this->processTour($item);
+    }
+
+    /**
+     * Return a tour and its steps or null if not found
+     *
+     * @param   TourTable  $item  The tour to load
+     *
+     * @return null|object
+     *
+     * @since   5.0.0
+     */
+    private function processTour($item)
+    {
+        $app = $this->getApplication();
+
+        $user    = $app->getIdentity();
+        $factory = $app->bootComponent('com_guidedtours')->getMVCFactory();
+
+        if (empty($item->id) || $item->published < 1 || !\in_array($item->access, $user->getAuthorisedViewLevels())) {
+            return null;
+        }
+
+        // We don't want to show all parameters, so take only a subset of the tour attributes
+        $tour = new \stdClass();
+
+        $tour->id = $item->id;
+
+        $stepsModel = $factory->createModel(
+            'Steps',
+            'Administrator',
+            ['ignore_request' => true]
+        );
+
+        $stepsModel->setState('filter.tour_id', $item->id);
+        $stepsModel->setState('filter.published', 1);
+        $stepsModel->setState('list.ordering', 'a.ordering');
+        $stepsModel->setState('list.direction', 'ASC');
+
+        $steps = $stepsModel->getItems();
+
+        $tour->steps = [];
+
+        $temp = new \stdClass();
+
+        $temp->id          = 0;
+        $temp->title       = $this->getApplication()->getLanguage()->_($item->title);
+        $temp->description = $this->getApplication()->getLanguage()->_($item->description);
+        $temp->url         = $item->url;
+
+        // Replace 'images/' to '../images/' when using an image from /images in backend.
+        $temp->description = preg_replace('*src\=\"(?!administrator\/)images/*', 'src="../images/', $temp->description);
+
+        $tour->steps[] = $temp;
+
+        foreach ($steps as $i => $step) {
+            $temp = new \stdClass();
+
+            $temp->id               = $i + 1;
+            $temp->title            = $this->getApplication()->getLanguage()->_($step->title);
+            $temp->description      = $this->getApplication()->getLanguage()->_($step->description);
+            $temp->position         = $step->position;
+            $temp->target           = $step->target;
+            $temp->type             = $this->stepType[$step->type];
+            $temp->interactive_type = $this->stepInteractiveType[$step->interactive_type];
+            $temp->url              = $step->url;
+            $temp->tour_id          = $step->tour_id;
+            $temp->step_id          = $step->id;
+
+            // Replace 'images/' to '../images/' when using an image from /images in backend.
+            $temp->description = preg_replace('*src\=\"(?!administrator\/)images/*', 'src="../images/', $temp->description);
+
+            $tour->steps[] = $temp;
+        }
+
+        return $tour;
+    }
+}

plugins/system/highlight/highlight.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_highlight</name>
+	<author>Joomla! Project</author>
+	<creationDate>2011-08</creationDate>
+	<copyright>(C) 2011 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see	LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SYSTEM_HIGHLIGHT_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Highlight</namespace>
+	<files>
+		<folder plugin="highlight">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_highlight.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_highlight.sys.ini</language>
+	</languages>
+</extension>

plugins/system/highlight/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.highlight
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Highlight\Extension\Highlight;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Highlight(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'highlight')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/highlight/src/Extension/Highlight.php

@@ -0,0 +1,127 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.highlight
+ *
+ * @copyright   (C) 2011 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Highlight\Extension;
+
+use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Filter\InputFilter;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\Component\Finder\Administrator\Indexer\Result;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * System plugin to highlight terms.
+ *
+ * @since  2.5
+ */
+final class Highlight extends CMSPlugin
+{
+    /**
+     * Method to catch the onAfterDispatch event.
+     *
+     * This is where we setup the click-through content highlighting for.
+     * The highlighting is done with JavaScript so we just
+     * need to check a few parameters and the JHtml behavior will do the rest.
+     *
+     * @return  void
+     *
+     * @since   2.5
+     */
+    public function onAfterDispatch()
+    {
+        // Check that we are in the site application.
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        // Set the variables.
+        $input     = $this->getApplication()->getInput();
+        $extension = $input->get('option', '', 'cmd');
+
+        // Check if the highlighter is enabled.
+        if (!ComponentHelper::getParams($extension)->get('highlight_terms', 1)) {
+            return;
+        }
+
+        // Check if the highlighter should be activated in this environment.
+        if ($input->get('tmpl', '', 'cmd') === 'component' || $this->getApplication()->getDocument()->getType() !== 'html') {
+            return;
+        }
+
+        // Get the terms to highlight from the request.
+        $terms = $input->request->get('highlight', null, 'base64');
+        $terms = $terms ? json_decode(base64_decode($terms)) : null;
+
+        // Check the terms.
+        if (empty($terms)) {
+            return;
+        }
+
+        // Clean the terms array.
+        $filter     = InputFilter::getInstance();
+
+        $cleanTerms = [];
+
+        foreach ($terms as $term) {
+            $cleanTerms[] = htmlspecialchars($filter->clean($term, 'string'));
+        }
+
+        /** @var \Joomla\CMS\Document\HtmlDocument $doc */
+        $doc = $this->getApplication()->getDocument();
+
+        // Activate the highlighter.
+        if (!empty($cleanTerms)) {
+            $doc->getWebAssetManager()->useScript('highlight');
+            $doc->addScriptOptions(
+                'highlight',
+                [[
+                    'class'     => 'js-highlight',
+                    'highLight' => $cleanTerms,
+                ]]
+            );
+        }
+
+        // Adjust the component buffer.
+        $buf = $doc->getBuffer('component');
+        $buf = '<div class="js-highlight">' . $buf . '</div>';
+        $doc->setBuffer($buf, 'component');
+    }
+
+    /**
+     * Method to catch the onFinderResult event.
+     *
+     * @param   Result  $item   The search result
+     * @param   object  $query  The search query of this result
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onFinderResult($item, $query)
+    {
+        static $params;
+
+        if (\is_null($params)) {
+            $params = ComponentHelper::getParams('com_finder');
+        }
+
+        // Get the route with highlighting information.
+        if (
+            !empty($query->highlight)
+            && empty($item->mime)
+            && $params->get('highlight_terms', 1)
+        ) {
+            $item->route .= '&highlight=' . base64_encode(json_encode($query->highlight));
+        }
+    }
+}

plugins/system/httpheaders/httpheaders.xml

@@ -0,0 +1,328 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_httpheaders</name>
+	<author>Joomla! Project</author>
+	<creationDate>2017-10</creationDate>
+	<copyright>(C) 2018 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.0.0</version>
+	<description>PLG_SYSTEM_HTTPHEADERS_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Httpheaders</namespace>
+	<files>
+		<folder>postinstall</folder>
+		<folder plugin="httpheaders">services</folder>
+		<folder>src</folder>
+	</files>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="xframeoptions"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_XFRAMEOPTIONS"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					filter="integer"
+					validate="options"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="referrerpolicy"
+					type="list"
+					label="PLG_SYSTEM_HTTPHEADERS_REFERRERPOLICY"
+					default="strict-origin-when-cross-origin"
+					validate="options"
+					>
+					<option value="disabled">JDISABLED</option>
+					<option value="no-referrer">no-referrer</option>
+					<option value="no-referrer-when-downgrade">no-referrer-when-downgrade</option>
+					<option value="origin">origin</option>
+					<option value="origin-when-cross-origin">origin-when-cross-origin</option>
+					<option value="same-origin">same-origin</option>
+					<option value="strict-origin">strict-origin</option>
+					<option value="strict-origin-when-cross-origin">strict-origin-when-cross-origin</option>
+					<option value="unsafe-url">unsafe-url</option>
+				</field>
+				<field
+					name="coop"
+					type="list"
+					label="PLG_SYSTEM_HTTPHEADERS_COOP"
+					default="same-origin"
+					validate="options"
+					>
+					<option value="disabled">JDISABLED</option>
+					<option value="same-origin">same-origin</option>
+					<option value="same-origin-allow-popups">same-origin-allow-popups</option>
+					<option value="unsafe-none">unsafe-none</option>
+				</field>
+				<field
+					name="additional_httpheader"
+					type="subform"
+					label="PLG_SYSTEM_HTTPHEADERS_ADDITIONAL_HEADER"
+					multiple="true"
+					>
+					<form>
+						<field
+							name="key"
+							type="list"
+							label="PLG_SYSTEM_HTTPHEADERS_ADDITIONAL_HEADER_KEY"
+							validate="options"
+							class="col-md-4"
+							>
+							<option value="content-security-policy">Content-Security-Policy</option>
+							<option value="content-security-policy-report-only">Content-Security-Policy-Report-Only</option>
+							<option value="cross-origin-opener-policy">Cross-Origin-Opener-Policy</option>
+							<option value="expect-ct">Expect-CT</option>
+							<option value="feature-policy">Feature-Policy</option>
+							<option value="nel">NEL</option>
+							<option value="permissions-policy">Permissions-Policy</option>
+							<option value="referrer-policy">Referrer-Policy</option>
+							<option value="report-to">Report-To</option>
+							<option value="strict-transport-security">Strict-Transport-Security</option>
+							<option value="x-frame-options">X-Frame-Options</option>
+						</field>
+						<field
+							name="value"
+							type="text"
+							label="PLG_SYSTEM_HTTPHEADERS_ADDITIONAL_HEADER_VALUE"
+							class="col-md-10"
+						/>
+						<field
+							name="client"
+							type="radio"
+							label="PLG_SYSTEM_HTTPHEADERS_HEADER_CLIENT"
+							default="site"
+							validate="options"
+							class="col-md-12"
+							>
+							<option value="site">JSITE</option>
+							<option value="administrator">JADMINISTRATOR</option>
+							<option value="both">PLG_SYSTEM_HTTPHEADERS_HEADER_CLIENT_BOTH</option>
+						</field>
+					</form>
+				</field>
+			</fieldset>
+			<fieldset name="hsts" label="Strict-Transport-Security (HSTS)">
+				<field
+					name="hsts"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_HSTS"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					validate="options"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="hsts_maxage"
+					type="number"
+					label="PLG_SYSTEM_HTTPHEADERS_HSTS_MAXAGE"
+					description="PLG_SYSTEM_HTTPHEADERS_HSTS_MAXAGE_DESC"
+					default="31536000"
+					filter="integer"
+					validate="number"
+					min="300"
+					showon="hsts:1"
+				/>
+				<field
+					name="hsts_subdomains"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_HSTS_SUBDOMAINS"
+					description="PLG_SYSTEM_HTTPHEADERS_HSTS_SUBDOMAINS_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					validate="options"
+					showon="hsts:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="hsts_preload"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_HSTS_PRELOAD"
+					description="PLG_SYSTEM_HTTPHEADERS_HSTS_PRELOAD_NOTE_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					validate="options"
+					showon="hsts:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+			</fieldset>
+			<fieldset name="csp" label="Content-Security-Policy (CSP)">
+				<field
+					name="contentsecuritypolicy"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="contentsecuritypolicy_client"
+					type="list"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_CLIENT"
+					default="site"
+					validate="options"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="site">JSITE</option>
+					<option value="administrator">JADMINISTRATOR</option>
+					<option value="both">PLG_SYSTEM_HTTPHEADERS_HEADER_CLIENT_BOTH</option>
+				</field>
+				<field
+					name="contentsecuritypolicy_report_only"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_REPORT_ONLY"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_REPORT_ONLY_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="nonce_enabled"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_NONCE_ENABLED"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_NONCE_ENABLED_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="script_hashes_enabled"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_SCRIPT_HASHES_ENABLED"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_SCRIPT_HASHES_ENABLED_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="strict_dynamic_enabled"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_STRICT_DYNAMIC_ENABLED"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_STRICT_DYNAMIC_ENABLED_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="style_hashes_enabled"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_STYLE_HASHES_ENABLED"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_STYLE_HASHES_ENABLED_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="frame_ancestors_self_enabled"
+					type="radio"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_FRAME_ANCESTORS_SELF_ENABLED"
+					description="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_FRAME_ANCESTORS_SELF_ENABLED_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					showon="contentsecuritypolicy:1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="contentsecuritypolicy_values"
+					type="subform"
+					label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_VALUES"
+					multiple="true"
+					showon="contentsecuritypolicy:1"
+					>
+					<form>
+						<field
+							name="directive"
+							type="list"
+							label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_VALUES_DIRECTIVE"
+							class="col-md-4"
+							validate="options"
+							>
+							<option value="child-src">child-src</option>
+							<option value="connect-src">connect-src</option>
+							<option value="default-src">default-src</option>
+							<option value="font-src">font-src</option>
+							<option value="frame-src">frame-src</option>
+							<option value="img-src">img-src</option>
+							<option value="manifest-src">manifest-src</option>
+							<option value="media-src">media-src</option>
+							<option value="prefetch-src">prefetch-src</option>
+							<option value="object-src">object-src</option>
+							<option value="script-src">script-src</option>
+							<option value="script-src-elem">script-src-elem</option>
+							<option value="script-src-attr">script-src-attr</option>
+							<option value="style-src">style-src</option>
+							<option value="style-src-elem">style-src-elem</option>
+							<option value="style-src-attr">style-src-attr</option>
+							<option value="worker-src">worker-src</option>
+							<option value="base-uri">base-uri</option>
+							<option value="plugin-types">plugin-types</option>
+							<option value="sandbox">sandbox</option>
+							<option value="form-action">form-action</option>
+							<option value="frame-ancestors">frame-ancestors</option>
+							<option value="navigate-to">navigate-to</option>
+							<option value="report-uri">report-uri</option>
+							<option value="report-to">report-to</option>
+							<option value="block-all-mixed-content">block-all-mixed-content</option>
+							<option value="upgrade-insecure-requests">upgrade-insecure-requests</option>
+							<option value="require-sri-for">require-sri-for</option>
+						</field>
+						<field
+							name="value"
+							type="text"
+							label="PLG_SYSTEM_HTTPHEADERS_CONTENTSECURITYPOLICY_VALUES_VALUE"
+							class="col-md-10"
+							showon="directive!:block-all-mixed-content[AND]directive!:upgrade-insecure-requests"
+						/>
+						<field
+							name="client"
+							type="radio"
+							label="PLG_SYSTEM_HTTPHEADERS_HEADER_CLIENT"
+							default="site"
+							class="col-md-12"
+							>
+							<option value="site">JSITE</option>
+							<option value="administrator">JADMINISTRATOR</option>
+							<option value="both">PLG_SYSTEM_HTTPHEADERS_HEADER_CLIENT_BOTH</option>
+						</field>
+					</form>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_httpheaders.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_httpheaders.sys.ini</language>
+	</languages>
+</extension>

plugins/system/httpheaders/postinstall/introduction.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.HttpHeaders
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+use Joomla\CMS\Factory;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Checks if the plugin is enabled. If not it returns true, meaning that the
+ * message concerning the HTTPHeaders Plugin should be displayed.
+ *
+ * @return  integer
+ *
+ * @since   4.0.0
+ */
+function httpheaders_postinstall_condition()
+{
+    return !Joomla\CMS\Plugin\PluginHelper::isEnabled('system', 'httpheaders');
+}
+
+/**
+ * Enables the HTTPHeaders plugin
+ *
+ * @return  void
+ *
+ * @since   4.0.0
+ */
+function httpheaders_postinstall_action()
+{
+    // Enable the plugin
+    $db = Factory::getDbo();
+
+    $query = $db->getQuery(true)
+        ->update($db->quoteName('#__extensions'))
+        ->set($db->quoteName('enabled') . ' = 1')
+        ->where($db->quoteName('type') . ' = ' . $db->quote('plugin'))
+        ->where($db->quoteName('folder') . ' = ' . $db->quote('system'))
+        ->where($db->quoteName('element') . ' = ' . $db->quote('httpheaders'));
+    $db->setQuery($query);
+    $db->execute();
+
+    $query = $db->getQuery(true)
+        ->select('extension_id')
+        ->from($db->quoteName('#__extensions'))
+        ->where($db->quoteName('type') . ' = ' . $db->quote('plugin'))
+        ->where($db->quoteName('folder') . ' = ' . $db->quote('system'))
+        ->where($db->quoteName('element') . ' = ' . $db->quote('httpheaders'));
+    $db->setQuery($query);
+    $extensionId = $db->loadResult();
+
+    $url = 'index.php?option=com_plugins&task=plugin.edit&extension_id=' . $extensionId;
+    Factory::getApplication()->redirect($url);
+}

plugins/system/httpheaders/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.httpheaders
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Httpheaders\Extension\Httpheaders;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Httpheaders(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'httpheaders'),
+                    Factory::getApplication()
+                );
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/httpheaders/src/Extension/Httpheaders.php

@@ -0,0 +1,456 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.httpheaders
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Httpheaders\Extension;
+
+use Joomla\CMS\Application\CMSApplicationInterface;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Event\Event;
+use Joomla\Event\SubscriberInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Plugin class for HTTP Headers
+ *
+ * @since  4.0.0
+ */
+final class Httpheaders extends CMSPlugin implements SubscriberInterface
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * The generated csp nonce value
+     *
+     * @var    string
+     * @since  4.0.0
+     */
+    private $cspNonce;
+
+    /**
+     * The list of the supported HTTP headers
+     *
+     * @var    array
+     * @since  4.0.0
+     */
+    private $supportedHttpHeaders = [
+        'strict-transport-security',
+        'content-security-policy',
+        'content-security-policy-report-only',
+        'x-frame-options',
+        'referrer-policy',
+        'expect-ct',
+        'feature-policy',
+        'cross-origin-opener-policy',
+        'report-to',
+        'permissions-policy',
+        'nel',
+    ];
+
+    /**
+     * The list of valid directives based on: https://www.w3.org/TR/CSP3/#csp-directives
+     *
+     * @var    array
+     * @since  4.0.0
+     */
+    private $validDirectives = [
+        'child-src',
+        'connect-src',
+        'default-src',
+        'font-src',
+        'frame-src',
+        'img-src',
+        'manifest-src',
+        'media-src',
+        'prefetch-src',
+        'object-src',
+        'script-src',
+        'script-src-elem',
+        'script-src-attr',
+        'style-src',
+        'style-src-elem',
+        'style-src-attr',
+        'worker-src',
+        'base-uri',
+        'plugin-types',
+        'sandbox',
+        'form-action',
+        'frame-ancestors',
+        'navigate-to',
+        'report-uri',
+        'report-to',
+        'block-all-mixed-content',
+        'upgrade-insecure-requests',
+        'require-sri-for',
+    ];
+
+    /**
+     * The list of directives without a value
+     *
+     * @var    array
+     * @since  4.0.0
+     */
+    private $noValueDirectives = [
+        'block-all-mixed-content',
+        'upgrade-insecure-requests',
+    ];
+
+    /**
+     * The list of directives supporting nonce
+     *
+     * @var    array
+     * @since  4.0.0
+     */
+    private $nonceDirectives = [
+        'script-src',
+        'style-src',
+    ];
+
+    /**
+     * @param   DispatcherInterface      $dispatcher  The object to observe -- event dispatcher.
+     * @param   array                    $config      An optional associative array of configuration settings.
+     * @param   CMSApplicationInterface  $app         The app
+     *
+     * @since   4.0.0
+     */
+    public function __construct(DispatcherInterface $dispatcher, array $config, CMSApplicationInterface $app)
+    {
+        parent::__construct($dispatcher, $config);
+
+        $this->setApplication($app);
+
+        $nonceEnabled = (int) $this->params->get('nonce_enabled', 0);
+
+        // Nonce generation when it's enabled
+        if ($nonceEnabled) {
+            $this->cspNonce = base64_encode(bin2hex(random_bytes(64)));
+        }
+
+        // Set the nonce, when not set we set it to NULL which is checked down the line
+        $this->getApplication()->set('csp_nonce', $this->cspNonce);
+    }
+
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return  array
+     *
+     * @since   4.0.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onAfterInitialise' => 'setHttpHeaders',
+            'onAfterRender'     => 'applyHashesToCspRule',
+        ];
+    }
+
+    /**
+     * The `applyHashesToCspRule` method makes sure the csp hashes are added to the csp header when enabled
+     *
+     * @param   Event  $event
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function applyHashesToCspRule(Event $event): void
+    {
+        // CSP is only relevant on html pages. Let's early exit here.
+        if ($this->getApplication()->getDocument()->getType() !== 'html') {
+            return;
+        }
+
+        $scriptHashesEnabled = (int) $this->params->get('script_hashes_enabled', 0);
+        $styleHashesEnabled  = (int) $this->params->get('style_hashes_enabled', 0);
+
+        // Early exit when both options are disabled
+        if (!$scriptHashesEnabled && !$styleHashesEnabled) {
+            return;
+        }
+
+        $headData     = $this->getApplication()->getDocument()->getHeadData();
+        $scriptHashes = [];
+        $styleHashes  = [];
+
+        if ($scriptHashesEnabled) {
+            // Generate the hashes for the script-src
+            $inlineScripts = \is_array($headData['script']) ? $headData['script'] : [];
+
+            foreach ($inlineScripts as $type => $scripts) {
+                foreach ($scripts as $hash => $scriptContent) {
+                    $scriptHashes[] = "'sha256-" . base64_encode(hash('sha256', $scriptContent, true)) . "'";
+                }
+            }
+        }
+
+        if ($styleHashesEnabled) {
+            // Generate the hashes for the style-src
+            $inlineStyles = \is_array($headData['style']) ? $headData['style'] : [];
+
+            foreach ($inlineStyles as $type => $styles) {
+                foreach ($styles as $hash => $styleContent) {
+                    $styleHashes[] = "'sha256-" . base64_encode(hash('sha256', $styleContent, true)) . "'";
+                }
+            }
+        }
+
+        // Replace the hashes in the csp header when set.
+        $headers = $this->getApplication()->getHeaders();
+
+        foreach ($headers as $id => $headerConfiguration) {
+            if (
+                strtolower($headerConfiguration['name']) === 'content-security-policy'
+                || strtolower($headerConfiguration['name']) === 'content-security-policy-report-only'
+            ) {
+                $newHeaderValue = $headerConfiguration['value'];
+
+                if (!empty($scriptHashes)) {
+                    $newHeaderValue = str_replace('{script-hashes}', implode(' ', $scriptHashes), $newHeaderValue);
+                } else {
+                    $newHeaderValue = str_replace('{script-hashes}', '', $newHeaderValue);
+                }
+
+                if (!empty($styleHashes)) {
+                    $newHeaderValue = str_replace('{style-hashes}', implode(' ', $styleHashes), $newHeaderValue);
+                } else {
+                    $newHeaderValue = str_replace('{style-hashes}', '', $newHeaderValue);
+                }
+
+                $this->getApplication()->setHeader($headerConfiguration['name'], $newHeaderValue, true);
+            }
+        }
+    }
+
+    /**
+     * The `setHttpHeaders` method handle the setting of the configured HTTP Headers
+     *
+     * @param   Event  $event
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function setHttpHeaders(Event $event): void
+    {
+        // Set the default header when they are enabled
+        $this->setStaticHeaders();
+
+        // Handle CSP Header configuration
+        $cspEnabled = (int) $this->params->get('contentsecuritypolicy', 0);
+        $cspClient  = (string) $this->params->get('contentsecuritypolicy_client', 'site');
+
+        // Check whether CSP is enabled and enabled by the current client
+        if ($cspEnabled && ($this->getApplication()->isClient($cspClient) || $cspClient === 'both')) {
+            $this->setCspHeader();
+        }
+    }
+
+    /**
+     * Set the CSP header when enabled
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    private function setCspHeader(): void
+    {
+        $cspReadOnly = (int) $this->params->get('contentsecuritypolicy_report_only', 1);
+        $cspHeader   = $cspReadOnly === 0 ? 'content-security-policy' : 'content-security-policy-report-only';
+
+        // In custom mode we compile the header from the values configured
+        $cspValues                 = $this->params->get('contentsecuritypolicy_values', []);
+        $nonceEnabled              = (int) $this->params->get('nonce_enabled', 0);
+        $scriptHashesEnabled       = (int) $this->params->get('script_hashes_enabled', 0);
+        $strictDynamicEnabled      = (int) $this->params->get('strict_dynamic_enabled', 0);
+        $styleHashesEnabled        = (int) $this->params->get('style_hashes_enabled', 0);
+        $frameAncestorsSelfEnabled = (int) $this->params->get('frame_ancestors_self_enabled', 1);
+        $frameAncestorsSet         = false;
+
+        foreach ($cspValues as $cspValue) {
+            // Handle the client settings foreach header
+            if (!$this->getApplication()->isClient($cspValue->client) && $cspValue->client != 'both') {
+                continue;
+            }
+
+            // Handle non value directives
+            if (\in_array($cspValue->directive, $this->noValueDirectives)) {
+                $newCspValues[] = trim($cspValue->directive);
+
+                continue;
+            }
+
+            // We can only use this if this is a valid entry
+            if (
+                \in_array($cspValue->directive, $this->validDirectives)
+                && !empty($cspValue->value)
+            ) {
+                if (\in_array($cspValue->directive, $this->nonceDirectives) && $nonceEnabled) {
+                    /**
+                     * That line is for B/C we do no longer require to add the nonce tag
+                     * but add it once the setting is enabled so this line here is needed
+                     * to remove the outdated tag that was required until 4.2.0
+                     */
+                    $cspValue->value = str_replace('{nonce}', '', $cspValue->value);
+
+                    // Append the nonce when the nonce setting is enabled
+                    $cspValue->value = "'nonce-" . $this->cspNonce . "' " . $cspValue->value;
+                }
+
+                // Append the script hashes placeholder
+                if ($scriptHashesEnabled && strpos($cspValue->directive, 'script-src') === 0) {
+                    $cspValue->value = '{script-hashes} ' . $cspValue->value;
+                }
+
+                // Append the style hashes placeholder
+                if ($styleHashesEnabled && strpos($cspValue->directive, 'style-src') === 0) {
+                    $cspValue->value = '{style-hashes} ' . $cspValue->value;
+                }
+
+                if ($cspValue->directive === 'frame-ancestors') {
+                    $frameAncestorsSet = true;
+                }
+
+                // Add strict-dynamic to the script-src directive when enabled
+                if (
+                    $strictDynamicEnabled
+                    && $cspValue->directive === 'script-src'
+                    && strpos($cspValue->value, 'strict-dynamic') === false
+                ) {
+                    $cspValue->value = "'strict-dynamic' " . $cspValue->value;
+                }
+
+                $newCspValues[] = trim($cspValue->directive) . ' ' . trim($cspValue->value);
+            }
+        }
+
+        if ($frameAncestorsSelfEnabled && !$frameAncestorsSet) {
+            $newCspValues[] = "frame-ancestors 'self'";
+        }
+
+        if (empty($newCspValues)) {
+            return;
+        }
+
+        $this->getApplication()->setHeader($cspHeader, trim(implode('; ', $newCspValues)));
+    }
+
+    /**
+     * Get the configured static headers.
+     *
+     * @return  array  We return the array of static headers with its values.
+     *
+     * @since   4.0.0
+     */
+    private function getStaticHeaderConfiguration(): array
+    {
+        $staticHeaderConfiguration = [];
+
+        // X-frame-options
+        if ($this->params->get('xframeoptions', 1) === 1) {
+            $staticHeaderConfiguration['x-frame-options#both'] = 'SAMEORIGIN';
+        }
+
+        // Referrer-policy
+        $referrerPolicy = (string) $this->params->get('referrerpolicy', 'strict-origin-when-cross-origin');
+
+        if ($referrerPolicy !== 'disabled') {
+            $staticHeaderConfiguration['referrer-policy#both'] = $referrerPolicy;
+        }
+
+        // Cross-Origin-Opener-Policy
+        $coop = (string) $this->params->get('coop', 'same-origin');
+
+        if ($coop !== 'disabled') {
+            $staticHeaderConfiguration['cross-origin-opener-policy#both'] = $coop;
+        }
+
+        // Generate the strict-transport-security header and make sure the site is SSL
+        if ($this->params->get('hsts', 0) === 1 && Uri::getInstance()->isSsl() === true) {
+            $hstsOptions   = [];
+            $hstsOptions[] = 'max-age=' . (int) $this->params->get('hsts_maxage', 31536000);
+
+            if ($this->params->get('hsts_subdomains', 0) === 1) {
+                $hstsOptions[] = 'includeSubDomains';
+            }
+
+            if ($this->params->get('hsts_preload', 0) === 1) {
+                $hstsOptions[] = 'preload';
+            }
+
+            $staticHeaderConfiguration['strict-transport-security#both'] = implode('; ', $hstsOptions);
+        }
+
+        // Generate the additional headers
+        $additionalHttpHeaders = $this->params->get('additional_httpheader', []);
+
+        foreach ($additionalHttpHeaders as $additionalHttpHeader) {
+            // Make sure we have a key and a value
+            if (empty($additionalHttpHeader->key) || empty($additionalHttpHeader->value)) {
+                continue;
+            }
+
+            // Make sure the header is a valid and supported header
+            if (!\in_array(strtolower($additionalHttpHeader->key), $this->supportedHttpHeaders)) {
+                continue;
+            }
+
+            // Make sure we do not add one header twice but we support to set a different header per client.
+            if (
+                isset($staticHeaderConfiguration[$additionalHttpHeader->key . '#' . $additionalHttpHeader->client])
+                || isset($staticHeaderConfiguration[$additionalHttpHeader->key . '#both'])
+            ) {
+                continue;
+            }
+
+            // Allow the custom csp headers to use the random $cspNonce in the rules
+            if (\in_array(strtolower($additionalHttpHeader->key), ['content-security-policy', 'content-security-policy-report-only'])) {
+                $additionalHttpHeader->value = str_replace('{nonce}', "'nonce-" . $this->cspNonce . "'", $additionalHttpHeader->value);
+            }
+
+            $staticHeaderConfiguration[$additionalHttpHeader->key . '#' . $additionalHttpHeader->client] = $additionalHttpHeader->value;
+        }
+
+        return $staticHeaderConfiguration;
+    }
+
+    /**
+     * Set the static headers when enabled
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    private function setStaticHeaders(): void
+    {
+        $staticHeaderConfiguration = $this->getStaticHeaderConfiguration();
+
+        if (empty($staticHeaderConfiguration)) {
+            return;
+        }
+
+        foreach ($staticHeaderConfiguration as $headerAndClient => $value) {
+            $headerAndClient = explode('#', $headerAndClient);
+            $header          = $headerAndClient[0];
+            $client          = $headerAndClient[1] ?? 'both';
+
+            if (!$this->getApplication()->isClient($client) && $client != 'both') {
+                continue;
+            }
+
+            $this->getApplication()->setHeader($header, $value, true);
+        }
+    }
+}

plugins/system/jooa11y/jooa11y.xml

@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_jooa11y</name>
+	<author>Joomla! Project</author>
+	<creationDate>2022-02</creationDate>
+	<copyright>(C) 2021 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.2.0</version>
+	<description>PLG_SYSTEM_JOOA11Y_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Jooa11y</namespace>
+	<files>
+		<folder plugin="jooa11y">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_jooa11y.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_jooa11y.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="showAlways"
+					type="radio"
+					label="PLG_SYSTEM_JOOA11Y_FIELD_SHOW_ALWAYS"
+					description="PLG_SYSTEM_JOOA11Y_FIELD_SHOW_ALWAYS_DESC"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					filter="integer"
+					>
+					<option value="0">JOFF</option>
+					<option value="1">JON</option>
+				</field>
+				<field
+					name="checkRoot"
+					type="text"
+					label="PLG_SYSTEM_JOOA11Y_FIELD_CHECK_ROOT"
+					description="PLG_SYSTEM_JOOA11Y_FIELD_CHECK_ROOT_DESC"
+					default="main"
+					filter="string"
+				/>
+				<field
+					name="readabilityRoot"
+					type="text"
+					label="PLG_SYSTEM_JOOA11Y_FIELD_READABILITY_ROOT"
+					description="PLG_SYSTEM_JOOA11Y_FIELD_READABILITY_ROOT_DESC"
+					default="main"
+					filter="string"
+				/>
+				<field
+					name="containerIgnore"
+					type="text"
+					label="PLG_SYSTEM_JOOA11Y_FIELD_CONTAINER_IGNORE"
+					description="PLG_SYSTEM_JOOA11Y_FIELD_CONTAINER_IGNORE_DESC"
+					filter="string"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/jooa11y/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.jooa11y
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Jooa11y\Extension\Jooa11y;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Jooa11y(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'jooa11y')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/jooa11y/src/Extension/Jooa11y.php

@@ -0,0 +1,259 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.jooa11y
+ *
+ * @copyright   (C) 2021 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Jooa11y\Extension;
+
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\Event\SubscriberInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Jooa11y plugin to add an accessibility checker
+ *
+ * @since  4.1.0
+ */
+final class Jooa11y extends CMSPlugin implements SubscriberInterface
+{
+    /**
+     * Subscribe to certain events
+     *
+     * @return string[]  An array of event mappings
+     *
+     * @since 4.1.0
+     *
+     * @throws Exception
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return ['onBeforeCompileHead' => 'initJooa11y'];
+    }
+
+    /**
+     * Method to check if the current user is allowed to see the debug information or not.
+     *
+     * @return  boolean  True if access is allowed.
+     *
+     * @since   4.1.0
+     */
+    private function isAuthorisedDisplayChecker(): bool
+    {
+        static $result;
+
+        if (\is_bool($result)) {
+            return $result;
+        }
+
+        // If the user is not allowed to view the output then end here.
+        $filterGroups = (array) $this->params->get('filter_groups', []);
+
+        if (!empty($filterGroups)) {
+            $userGroups = $this->getApplication()->getIdentity()->get('groups');
+
+            if (!array_intersect($filterGroups, $userGroups)) {
+                $result = false;
+
+                return $result;
+            }
+        }
+
+        $result = true;
+
+        return $result;
+    }
+
+    /**
+     * Add the checker.
+     *
+     * @return  void
+     *
+     * @since   4.1.0
+     */
+    public function initJooa11y()
+    {
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        // Check if we are in a preview modal or the plugin has enforced loading
+        $showJooa11y = $this->getApplication()->getInput()->get('jooa11y', $this->params->get('showAlways', 0));
+
+        // Load the checker if authorised
+        if (!$showJooa11y || !$this->isAuthorisedDisplayChecker()) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        // Get the document object.
+        $document = $this->getApplication()->getDocument();
+
+        // Add plugin settings from the xml
+        $document->addScriptOptions(
+            'jooa11yOptions',
+            [
+                'checkRoot'       => $this->params->get('checkRoot', 'main'),
+                'readabilityRoot' => $this->params->get('readabilityRoot', 'main'),
+                'containerIgnore' => $this->params->get('containerIgnore'),
+            ]
+        );
+
+        // Add the language constants
+        $constants = [
+            'PLG_SYSTEM_JOOA11Y_ALERT_CLOSE',
+            'PLG_SYSTEM_JOOA11Y_ALERT_TEXT',
+            'PLG_SYSTEM_JOOA11Y_AVG_WORD_PER_SENTENCE',
+            'PLG_SYSTEM_JOOA11Y_COMPLEX_WORDS',
+            'PLG_SYSTEM_JOOA11Y_CONTAINER_LABEL',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_ERROR_INPUT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_ERROR_INPUT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_ERROR_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_ERROR_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_WARNING_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_CONTRAST_WARNING_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_DARK_MODE',
+            'PLG_SYSTEM_JOOA11Y_DIFFICULT_READABILITY',
+            'PLG_SYSTEM_JOOA11Y_EMBED_AUDIO',
+            'PLG_SYSTEM_JOOA11Y_EMBED_GENERAL_WARNING',
+            'PLG_SYSTEM_JOOA11Y_EMBED_MISSING_TITLE',
+            'PLG_SYSTEM_JOOA11Y_EMBED_VIDEO',
+            'PLG_SYSTEM_JOOA11Y_ERROR',
+            'PLG_SYSTEM_JOOA11Y_FAIRLY_DIFFICULT_READABILITY',
+            'PLG_SYSTEM_JOOA11Y_FILE_TYPE_WARNING',
+            'PLG_SYSTEM_JOOA11Y_FILE_TYPE_WARNING_TIP',
+            'PLG_SYSTEM_JOOA11Y_FORM_LABELS',
+            'PLG_SYSTEM_JOOA11Y_GOOD',
+            'PLG_SYSTEM_JOOA11Y_GOOD_READABILITY',
+            'PLG_SYSTEM_JOOA11Y_HEADING_EMPTY',
+            'PLG_SYSTEM_JOOA11Y_HEADING_EMPTY_WITH_IMAGE',
+            'PLG_SYSTEM_JOOA11Y_HEADING_FIRST',
+            'PLG_SYSTEM_JOOA11Y_HEADING_LONG',
+            'PLG_SYSTEM_JOOA11Y_HEADING_LONG_INFO',
+            'PLG_SYSTEM_JOOA11Y_HEADING_MISSING_ONE',
+            'PLG_SYSTEM_JOOA11Y_HEADING_NON_CONSECUTIVE_LEVEL',
+            'PLG_SYSTEM_JOOA11Y_HIDE_OUTLINE',
+            'PLG_SYSTEM_JOOA11Y_HIDE_SETTINGS',
+            'PLG_SYSTEM_JOOA11Y_HYPERLINK_ALT_LENGTH_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_HYPERLINK_ALT_LENGTH_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_IMAGE_FIGURE_DECORATIVE',
+            'PLG_SYSTEM_JOOA11Y_IMAGE_FIGURE_DECORATIVE_INFO',
+            'PLG_SYSTEM_JOOA11Y_IMAGE_FIGURE_DUPLICATE_ALT',
+            'PLG_SYSTEM_JOOA11Y_LABELS_ARIA_LABEL_INPUT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LABELS_ARIA_LABEL_INPUT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LABELS_INPUT_RESET_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LABELS_INPUT_RESET_MESSAGE_TIP',
+            'PLG_SYSTEM_JOOA11Y_LABELS_MISSING_IMAGE_INPUT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LABELS_MISSING_LABEL_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LABELS_NO_FOR_ATTRIBUTE_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LABELS_NO_FOR_ATTRIBUTE_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LANG_CODE',
+            'PLG_SYSTEM_JOOA11Y_LINKS_ADVANCED',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_HAS_BAD_WORD_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_HAS_BAD_WORD_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_HAS_SUS_WORD_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_HAS_SUS_WORD_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_PLACEHOLDER_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_TOO_LONG_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_ALT_TOO_LONG_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_ANCHOR_LINK_AND_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_ANCHOR_LINK_AND_ALT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_BEST_PRACTICES',
+            'PLG_SYSTEM_JOOA11Y_LINK_BEST_PRACTICES_DETAILS',
+            'PLG_SYSTEM_JOOA11Y_LINK_DECORATIVE_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_EMPTY',
+            'PLG_SYSTEM_JOOA11Y_LINK_EMPTY_LINK_NO_LABEL',
+            'PLG_SYSTEM_JOOA11Y_LINK_HYPERLINKED_IMAGE_ARIA_HIDDEN',
+            'PLG_SYSTEM_JOOA11Y_LINK_IDENTICAL_NAME',
+            'PLG_SYSTEM_JOOA11Y_LINK_IDENTICAL_NAME_TIP',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_BAD_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_BAD_ALT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_LINK_ALT_TEXT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_LINK_ALT_TEXT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_LINK_NULL_ALT_NO_TEXT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_PLACEHOLDER_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_SUS_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_IMAGE_SUS_ALT_MESSAGE_INFO',
+            'PLG_SYSTEM_JOOA11Y_LINK_LABEL',
+            'PLG_SYSTEM_JOOA11Y_LINK_LINK_HAS_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_LINK_PASS_ALT',
+            'PLG_SYSTEM_JOOA11Y_LINK_STOPWORD',
+            'PLG_SYSTEM_JOOA11Y_LINK_STOPWORD_TIP',
+            'PLG_SYSTEM_JOOA11Y_LINK_URL',
+            'PLG_SYSTEM_JOOA11Y_LINK_URL_TIP',
+            'PLG_SYSTEM_JOOA11Y_MAIN_TOGGLE_LABEL',
+            'PLG_SYSTEM_JOOA11Y_MISSING_ALT_LINK_BUT_HAS_TEXT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_MISSING_ALT_LINK_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_MISSING_ALT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_NEW_TAB_WARNING',
+            'PLG_SYSTEM_JOOA11Y_NEW_TAB_WARNING_TIP',
+            'PLG_SYSTEM_JOOA11Y_OFF',
+            'PLG_SYSTEM_JOOA11Y_ON',
+            'PLG_SYSTEM_JOOA11Y_PAGE_OUTLINE',
+            'PLG_SYSTEM_JOOA11Y_PANEL_HEADING_MISSING_ONE',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_BOTH',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_ERRORS',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_HIDDEN',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_ICON',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_NONE',
+            'PLG_SYSTEM_JOOA11Y_PANEL_STATUS_WARNINGS',
+            'PLG_SYSTEM_JOOA11Y_QA_BAD_ITALICS',
+            'PLG_SYSTEM_JOOA11Y_QA_BAD_LINK',
+            'PLG_SYSTEM_JOOA11Y_QA_BLOCKQUOTE_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_QA_BLOCKQUOTE_MESSAGE_TIP',
+            'PLG_SYSTEM_JOOA11Y_QA_DUPLICATE_ID',
+            'PLG_SYSTEM_JOOA11Y_QA_DUPLICATE_ID_TIP',
+            'PLG_SYSTEM_JOOA11Y_QA_FAKE_HEADING',
+            'PLG_SYSTEM_JOOA11Y_QA_FAKE_HEADING_INFO',
+            'PLG_SYSTEM_JOOA11Y_QA_PAGE_LANGUAGE_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_QA_PDF_COUNT',
+            'PLG_SYSTEM_JOOA11Y_QA_SHOULD_BE_LIST',
+            'PLG_SYSTEM_JOOA11Y_QA_SHOULD_BE_LIST_TIP',
+            'PLG_SYSTEM_JOOA11Y_QA_UPPERCASE_WARNING',
+            'PLG_SYSTEM_JOOA11Y_READABILITY',
+            'PLG_SYSTEM_JOOA11Y_READABILITY_NOT_ENOUGH_CONTENT_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_READABILITY_NO_P_OR_LI_MESSAGE',
+            'PLG_SYSTEM_JOOA11Y_SETTINGS',
+            'PLG_SYSTEM_JOOA11Y_SHORTCUT_SR',
+            'PLG_SYSTEM_JOOA11Y_SHORTCUT_TOOLTIP',
+            'PLG_SYSTEM_JOOA11Y_SHOW_OUTLINE',
+            'PLG_SYSTEM_JOOA11Y_SHOW_SETTINGS',
+            'PLG_SYSTEM_JOOA11Y_TABLES_EMPTY_HEADING',
+            'PLG_SYSTEM_JOOA11Y_TABLES_EMPTY_HEADING_INFO',
+            'PLG_SYSTEM_JOOA11Y_TABLES_MISSING_HEADINGS',
+            'PLG_SYSTEM_JOOA11Y_TABLES_MISSING_HEADINGS_INFO',
+            'PLG_SYSTEM_JOOA11Y_TABLES_SEMANTIC_HEADING',
+            'PLG_SYSTEM_JOOA11Y_TABLES_SEMANTIC_HEADING_INFO',
+            'PLG_SYSTEM_JOOA11Y_TEXT_UNDERLINE_WARNING',
+            'PLG_SYSTEM_JOOA11Y_TEXT_UNDERLINE_WARNING_TIP',
+            'PLG_SYSTEM_JOOA11Y_TOTAL_WORDS',
+            'PLG_SYSTEM_JOOA11Y_VERY_DIFFICULT_READABILITY',
+            'PLG_SYSTEM_JOOA11Y_WARNING',
+        ];
+
+        foreach ($constants as $constant) {
+            Text::script($constant);
+        }
+
+        /** @var Joomla\CMS\WebAsset\WebAssetManager $wa*/
+        $wa = $document->getWebAssetManager();
+
+        $wa->getRegistry()->addRegistryFile('media/plg_system_jooa11y/joomla.asset.json');
+
+        $wa->useScript('plg_system_jooa11y.jooa11y')
+            ->useStyle('plg_system_jooa11y.jooa11y');
+
+        return true;
+    }
+}

plugins/system/languagecode/languagecode.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_languagecode</name>
+	<author>Joomla! Project</author>
+	<creationDate>2011-11</creationDate>
+	<copyright>(C) 2011 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SYSTEM_LANGUAGECODE_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\LanguageCode</namespace>
+	<files>
+		<folder plugin="languagecode">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_languagecode.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_languagecode.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<field
+				name="languagecodeplugin"
+				type="hidden"
+				default="true"
+			/>
+		</fields>
+	</config>
+</extension>

plugins/system/languagecode/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.languagecode
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\LanguageCode\Extension\LanguageCode;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new LanguageCode(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'languagecode')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/languagecode/src/Extension/LanguageCode.php

@@ -0,0 +1,151 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.languagecode
+ *
+ * @copyright   (C) 2011 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\LanguageCode\Extension;
+
+use Joomla\CMS\Form\Form;
+use Joomla\CMS\Language\LanguageHelper;
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Language Code plugin class.
+ *
+ * @since  2.5
+ */
+final class LanguageCode extends CMSPlugin
+{
+    /**
+     * Plugin that changes the language code used in the <html /> tag.
+     *
+     * @return  void
+     *
+     * @since   2.5
+     */
+    public function onAfterRender()
+    {
+        // Use this plugin only in site application.
+        if ($this->getApplication()->isClient('site')) {
+            // Get the response body.
+            $body = $this->getApplication()->getBody();
+
+            // Get the current language code.
+            $code = $this->getApplication()->getDocument()->getLanguage();
+
+            // Get the new code.
+            $new_code  = $this->params->get($code);
+
+            // Replace the old code by the new code in the <html /> tag.
+            if ($new_code) {
+                // Replace the new code in the HTML document.
+                $patterns = [
+                    \chr(1) . '(<html.*\s+xml:lang=")(' . $code . ')(".*>)' . \chr(1) . 'i',
+                    \chr(1) . '(<html.*\s+lang=")(' . $code . ')(".*>)' . \chr(1) . 'i',
+                ];
+                $replace = [
+                    '${1}' . strtolower($new_code) . '${3}',
+                    '${1}' . strtolower($new_code) . '${3}',
+                ];
+            } else {
+                $patterns = [];
+                $replace  = [];
+            }
+
+            // Replace codes in <link hreflang="" /> attributes.
+            preg_match_all(\chr(1) . '(<link.*\s+hreflang=")([0-9a-z\-]*)(".*\s+rel="alternate".*>)' . \chr(1) . 'i', $body, $matches);
+
+            foreach ($matches[2] as $match) {
+                $new_code = $this->params->get(strtolower($match));
+
+                if ($new_code) {
+                    $patterns[] = \chr(1) . '(<link.*\s+hreflang=")(' . $match . ')(".*\s+rel="alternate".*>)' . \chr(1) . 'i';
+                    $replace[]  = '${1}' . $new_code . '${3}';
+                }
+            }
+
+            preg_match_all(\chr(1) . '(<link.*\s+rel="alternate".*\s+hreflang=")([0-9A-Za-z\-]*)(".*>)' . \chr(1) . 'i', $body, $matches);
+
+            foreach ($matches[2] as $match) {
+                $new_code = $this->params->get(strtolower($match));
+
+                if ($new_code) {
+                    $patterns[] = \chr(1) . '(<link.*\s+rel="alternate".*\s+hreflang=")(' . $match . ')(".*>)' . \chr(1) . 'i';
+                    $replace[]  = '${1}' . $new_code . '${3}';
+                }
+            }
+
+            // Replace codes in itemprop content
+            preg_match_all(\chr(1) . '(<meta.*\s+itemprop="inLanguage".*\s+content=")([0-9A-Za-z\-]*)(".*>)' . \chr(1) . 'i', $body, $matches);
+
+            foreach ($matches[2] as $match) {
+                $new_code = $this->params->get(strtolower($match));
+
+                if ($new_code) {
+                    $patterns[] = \chr(1) . '(<meta.*\s+itemprop="inLanguage".*\s+content=")(' . $match . ')(".*>)' . \chr(1) . 'i';
+                    $replace[]  = '${1}' . $new_code . '${3}';
+                }
+            }
+
+            $this->getApplication()->setBody(preg_replace($patterns, $replace, $body));
+        }
+    }
+
+    /**
+     * Prepare form.
+     *
+     * @param   Form   $form  The form to be altered.
+     * @param   mixed  $data  The associated data for the form.
+     *
+     * @return  boolean
+     *
+     * @since   2.5
+     */
+    public function onContentPrepareForm(Form $form, $data)
+    {
+        // Check we are manipulating the languagecode plugin.
+        if ($form->getName() !== 'com_plugins.plugin' || !$form->getField('languagecodeplugin', 'params')) {
+            return true;
+        }
+
+        // Get site languages.
+        if ($languages = LanguageHelper::getKnownLanguages(JPATH_SITE)) {
+            // Inject fields into the form.
+            foreach ($languages as $tag => $language) {
+                $form->load('
+					<form>
+						<fields name="params">
+							<fieldset
+								name="languagecode"
+								label="PLG_SYSTEM_LANGUAGECODE_FIELDSET_LABEL"
+								description="PLG_SYSTEM_LANGUAGECODE_FIELDSET_DESC"
+							>
+								<field
+									name="' . strtolower($tag) . '"
+									type="text"
+									label="' . $tag . '"
+									description="' . htmlspecialchars(Text::sprintf('PLG_SYSTEM_LANGUAGECODE_FIELD_DESC', $language['name']), ENT_COMPAT, 'UTF-8') . '"
+									translate_description="false"
+									translate_label="false"
+									size="7"
+									filter="cmd"
+								/>
+							</fieldset>
+						</fields>
+					</form>');
+            }
+        }
+
+        return true;
+    }
+}

plugins/system/languagefilter/languagefilter.xml

@@ -0,0 +1,121 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_languagefilter</name>
+	<author>Joomla! Project</author>
+	<creationDate>2010-07</creationDate>
+	<copyright>(C) 2010 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SYSTEM_LANGUAGEFILTER_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\LanguageFilter</namespace>
+	<files>
+		<folder plugin="languagefilter">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_languagefilter.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_languagefilter.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="detect_browser"
+					type="list"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_DETECT_BROWSER_LABEL"
+					default="0"
+					filter="integer"
+					validate="options"
+					>
+					<option value="0">PLG_SYSTEM_LANGUAGEFILTER_SITE_LANGUAGE</option>
+					<option value="1">PLG_SYSTEM_LANGUAGEFILTER_BROWSER_SETTINGS</option>
+				</field>
+
+				<field
+					name="automatic_change"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_AUTOMATIC_CHANGE_LABEL"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="item_associations"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_ITEM_ASSOCIATIONS_LABEL"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="alternate_meta"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_ALTERNATE_META_LABEL"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="xdefault"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_XDEFAULT_LABEL"
+					default="1"
+					filter="integer"
+					showon="alternate_meta:1"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="xdefault_language"
+					type="contentlanguage"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_XDEFAULT_LANGUAGE_LABEL"
+					default="default"
+					showon="alternate_meta:1[AND]xdefault:1"
+					>
+					<option value="default">PLG_SYSTEM_LANGUAGEFILTER_OPTION_DEFAULT_LANGUAGE</option>
+				</field>
+
+				<field
+					name="remove_default_prefix"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_REMOVE_DEFAULT_PREFIX_LABEL"
+					default="0"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+
+				<field
+					name="lang_cookie"
+					type="list"
+					label="PLG_SYSTEM_LANGUAGEFILTER_FIELD_COOKIE_LABEL"
+					default="0"
+					filter="integer"
+					validate="options"
+					>
+					<option value="1">PLG_SYSTEM_LANGUAGEFILTER_OPTION_YEAR</option>
+					<option value="0">PLG_SYSTEM_LANGUAGEFILTER_OPTION_SESSION</option>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/languagefilter/services/provider.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.languagefilter
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Language\LanguageFactoryInterface;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\Router\SiteRouter;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\LanguageFilter\Extension\LanguageFilter;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin = new LanguageFilter(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'languagefilter'),
+                    Factory::getApplication(),
+                    $container->get(LanguageFactoryInterface::class)
+                );
+                $plugin->setSiteRouter($container->get(SiteRouter::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/languagefilter/src/Extension/LanguageFilter.php

@@ -0,0 +1,856 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.languagefilter
+ *
+ * @copyright   (C) 2010 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\LanguageFilter\Extension;
+
+use Joomla\CMS\Application\ApplicationHelper;
+use Joomla\CMS\Application\CMSApplicationInterface;
+use Joomla\CMS\Association\AssociationServiceInterface;
+use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Filesystem\Folder;
+use Joomla\CMS\Language\Associations;
+use Joomla\CMS\Language\LanguageFactoryInterface;
+use Joomla\CMS\Language\LanguageHelper;
+use Joomla\CMS\Language\Multilanguage;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Router\Router;
+use Joomla\CMS\Router\SiteRouterAwareTrait;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Component\Menus\Administrator\Helper\MenusHelper;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Filesystem\Path;
+use Joomla\Registry\Registry;
+use Joomla\String\StringHelper;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! Language Filter Plugin.
+ *
+ * @since  1.6
+ */
+final class LanguageFilter extends CMSPlugin
+{
+    use SiteRouterAwareTrait;
+
+    /**
+     * The routing mode.
+     *
+     * @var    boolean
+     * @since  2.5
+     */
+    protected $mode_sef;
+
+    /**
+     * Available languages by sef.
+     *
+     * @var    array
+     * @since  1.6
+     */
+    protected $sefs;
+
+    /**
+     * Available languages by language codes.
+     *
+     * @var    array
+     * @since  2.5
+     */
+    protected $lang_codes;
+
+    /**
+     * The current language code.
+     *
+     * @var    string
+     * @since  3.4.2
+     */
+    protected $current_lang;
+
+    /**
+     * The default language code.
+     *
+     * @var    string
+     * @since  2.5
+     */
+    protected $default_lang;
+
+    /**
+     * The logged user language code.
+     *
+     * @var    string
+     * @since  3.3.1
+     */
+    private $user_lang_code;
+
+    /**
+     * The language factory
+     *
+     * @var   LanguageFactoryInterface
+     *
+     * @since 4.4.0
+     */
+    private $languageFactory;
+
+    /**
+     * Constructor.
+     *
+     * @param   DispatcherInterface       $dispatcher       The dispatcher
+     * @param   array                     $config           An optional associative array of configuration settings
+     * @param   CMSApplicationInterface   $app              The language factory
+     * @param   LanguageFactoryInterface  $languageFactory  The language factory
+     *
+     * @since   1.6.0
+     */
+    public function __construct(
+        DispatcherInterface $dispatcher,
+        array $config,
+        CMSApplicationInterface $app,
+        LanguageFactoryInterface $languageFactory
+    ) {
+        parent::__construct($dispatcher, $config);
+
+        $this->languageFactory = $languageFactory;
+
+        $this->setApplication($app);
+
+        // Setup language data.
+        $this->mode_sef     = $this->getApplication()->get('sef', 0);
+        $this->sefs         = LanguageHelper::getLanguages('sef');
+        $this->lang_codes   = LanguageHelper::getLanguages('lang_code');
+        $this->default_lang = ComponentHelper::getParams('com_languages')->get('site', 'en-GB');
+
+        // If language filter plugin is executed in a site page.
+        if ($this->getApplication()->isClient('site')) {
+            $levels = $this->getApplication()->getIdentity()->getAuthorisedViewLevels();
+
+            foreach ($this->sefs as $sef => $language) {
+                // @todo: In Joomla 2.5.4 and earlier access wasn't set. Non modified Content Languages got 0 as access value
+                // we also check if frontend language exists and is enabled
+                if (
+                    ($language->access && !\in_array($language->access, $levels))
+                    || (!\array_key_exists($language->lang_code, LanguageHelper::getInstalledLanguages(0)))
+                ) {
+                    unset($this->lang_codes[$language->lang_code], $this->sefs[$language->sef]);
+                }
+            }
+        } else {
+            // If language filter plugin is executed in an admin page (ex: Route site).
+            // Set current language to default site language, fallback to en-GB if there is no content language for the default site language.
+            $this->current_lang = isset($this->lang_codes[$this->default_lang]) ? $this->default_lang : 'en-GB';
+
+            foreach ($this->sefs as $sef => $language) {
+                if (!\array_key_exists($language->lang_code, LanguageHelper::getInstalledLanguages(0))) {
+                    unset($this->lang_codes[$language->lang_code]);
+                    unset($this->sefs[$language->sef]);
+                }
+            }
+        }
+    }
+
+    /**
+     * After initialise.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function onAfterInitialise()
+    {
+        $router = $this->getSiteRouter();
+
+        // Attach build rules for language SEF.
+        $router->attachBuildRule([$this, 'preprocessBuildRule'], Router::PROCESS_BEFORE);
+
+        if ($this->mode_sef) {
+            $router->attachBuildRule([$this, 'buildRule'], Router::PROCESS_BEFORE);
+            $router->attachBuildRule([$this, 'postprocessSEFBuildRule'], Router::PROCESS_AFTER);
+        } else {
+            $router->attachBuildRule([$this, 'postprocessNonSEFBuildRule'], Router::PROCESS_AFTER);
+        }
+
+        // Attach parse rule.
+        $router->attachParseRule([$this, 'parseRule'], Router::PROCESS_BEFORE);
+    }
+
+    /**
+     * After route.
+     *
+     * @return  void
+     *
+     * @since   3.4
+     */
+    public function onAfterRoute()
+    {
+        // Add custom site name.
+        if ($this->getApplication()->isClient('site') && isset($this->lang_codes[$this->current_lang]) && $this->lang_codes[$this->current_lang]->sitename) {
+            $this->getApplication()->set('sitename', $this->lang_codes[$this->current_lang]->sitename);
+        }
+    }
+
+    /**
+     * Add build preprocess rule to router.
+     *
+     * @param   Router  &$router  Router object.
+     * @param   Uri     &$uri     Uri object.
+     *
+     * @return  void
+     *
+     * @since   3.4
+     */
+    public function preprocessBuildRule(&$router, &$uri)
+    {
+        $lang = $uri->getVar('lang', $this->current_lang);
+
+        if (isset($this->sefs[$lang])) {
+            $lang = $this->sefs[$lang]->lang_code;
+        }
+
+        $uri->setVar('lang', $lang);
+    }
+
+    /**
+     * Add build rule to router.
+     *
+     * @param   Router  &$router  Router object.
+     * @param   Uri     &$uri     Uri object.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function buildRule(&$router, &$uri)
+    {
+        $lang = $uri->getVar('lang');
+
+        if (isset($this->lang_codes[$lang])) {
+            $sef = $this->lang_codes[$lang]->sef;
+        } else {
+            $sef = $this->lang_codes[$this->current_lang]->sef;
+        }
+
+        if (
+            !$this->params->get('remove_default_prefix', 0)
+            || $lang !== $this->default_lang
+            || $lang !== $this->current_lang
+        ) {
+            $uri->setPath($uri->getPath() . '/' . $sef . '/');
+        }
+    }
+
+    /**
+     * postprocess build rule for SEF URLs
+     *
+     * @param   Router  &$router  Router object.
+     * @param   Uri     &$uri     Uri object.
+     *
+     * @return  void
+     *
+     * @since   3.4
+     */
+    public function postprocessSEFBuildRule(&$router, &$uri)
+    {
+        $uri->delVar('lang');
+    }
+
+    /**
+     * postprocess build rule for non-SEF URLs
+     *
+     * @param   Router  &$router  Router object.
+     * @param   Uri     &$uri     Uri object.
+     *
+     * @return  void
+     *
+     * @since   3.4
+     */
+    public function postprocessNonSEFBuildRule(&$router, &$uri)
+    {
+        $lang = $uri->getVar('lang');
+
+        if (isset($this->lang_codes[$lang])) {
+            $uri->setVar('lang', $this->lang_codes[$lang]->sef);
+        }
+    }
+
+    /**
+     * Add parse rule to router.
+     *
+     * @param   Router  &$router  Router object.
+     * @param   Uri     &$uri     Uri object.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function parseRule(&$router, &$uri)
+    {
+        // Did we find the current and existing language yet?
+        $found = false;
+
+        // Are we in SEF mode or not?
+        if ($this->mode_sef) {
+            $path  = $uri->getPath();
+            $parts = explode('/', $path);
+
+            $sef = StringHelper::strtolower($parts[0]);
+
+            // Do we have a URL Language Code ?
+            if (!isset($this->sefs[$sef])) {
+                // Check if remove default URL language code is set
+                if ($this->params->get('remove_default_prefix', 0)) {
+                    if ($parts[0]) {
+                        // We load a default site language page
+                        $lang_code = $this->default_lang;
+                    } else {
+                        // We check for an existing language cookie
+                        $lang_code = $this->getLanguageCookie();
+                    }
+                } else {
+                    $lang_code = $this->getLanguageCookie();
+                }
+
+                // No language code. Try using browser settings or default site language
+                if (!$lang_code && $this->params->get('detect_browser', 0) == 1) {
+                    $lang_code = LanguageHelper::detectLanguage();
+                }
+
+                if (!$lang_code) {
+                    $lang_code = $this->default_lang;
+                }
+
+                if ($lang_code === $this->default_lang && $this->params->get('remove_default_prefix', 0)) {
+                    $found = true;
+                }
+            } else {
+                // We found our language
+                $found     = true;
+                $lang_code = $this->sefs[$sef]->lang_code;
+
+                // If we found our language, but it's the default language and we don't want a prefix for that, we are on a wrong URL.
+                // Or we try to change the language back to the default language. We need a redirect to the proper URL for the default language.
+                if ($lang_code === $this->default_lang && $this->params->get('remove_default_prefix', 0)) {
+                    // Create a cookie.
+                    $this->setLanguageCookie($lang_code);
+
+                    $found = false;
+                    array_shift($parts);
+                    $path = implode('/', $parts);
+                }
+
+                // We have found our language and the first part of our URL is the language prefix
+                if ($found) {
+                    array_shift($parts);
+
+                    // Empty parts array when "index.php" is the only part left.
+                    if (\count($parts) === 1 && $parts[0] === 'index.php') {
+                        $parts = [];
+                    }
+
+                    $uri->setPath(implode('/', $parts));
+                }
+            }
+        } else {
+            // We are not in SEF mode
+            $lang_code = $this->getLanguageCookie();
+
+            if (!$lang_code && $this->params->get('detect_browser', 1)) {
+                $lang_code = LanguageHelper::detectLanguage();
+            }
+
+            if (!isset($this->lang_codes[$lang_code])) {
+                $lang_code = $this->default_lang;
+            }
+        }
+
+        $lang = $uri->getVar('lang', $lang_code);
+
+        if (isset($this->sefs[$lang])) {
+            // We found our language
+            $found     = true;
+            $lang_code = $this->sefs[$lang]->lang_code;
+        }
+
+        // We are called via POST or the nolangfilter url parameter was set. We don't care about the language
+        // and simply set the default language as our current language.
+        if (
+            $this->getApplication()->getInput()->getMethod() === 'POST'
+            || $this->getApplication()->getInput()->get('nolangfilter', 0) == 1
+            || \count($this->getApplication()->getInput()->post) > 0
+            || \count($this->getApplication()->getInput()->files) > 0
+        ) {
+            $found = true;
+
+            if (!isset($lang_code)) {
+                $lang_code = $this->getLanguageCookie();
+            }
+
+            if (!$lang_code && $this->params->get('detect_browser', 1)) {
+                $lang_code = LanguageHelper::detectLanguage();
+            }
+
+            if (!isset($this->lang_codes[$lang_code])) {
+                $lang_code = $this->default_lang;
+            }
+        }
+
+        // We have not found the language and thus need to redirect
+        if (!$found) {
+            // Lets find the default language for this user
+            if (!isset($lang_code) || !isset($this->lang_codes[$lang_code])) {
+                $lang_code = false;
+
+                if ($this->params->get('detect_browser', 1)) {
+                    $lang_code = LanguageHelper::detectLanguage();
+
+                    if (!isset($this->lang_codes[$lang_code])) {
+                        $lang_code = false;
+                    }
+                }
+
+                if (!$lang_code) {
+                    $lang_code = $this->default_lang;
+                }
+            }
+
+            if ($this->mode_sef) {
+                // Use the current language sef or the default one.
+                if (
+                    $lang_code !== $this->default_lang
+                    || !$this->params->get('remove_default_prefix', 0)
+                ) {
+                    $path = $this->lang_codes[$lang_code]->sef . '/' . $path;
+                }
+
+                $uri->setPath($path);
+
+                if (!$this->getApplication()->get('sef_rewrite')) {
+                    $uri->setPath('index.php/' . $uri->getPath());
+                }
+
+                $redirectUri = $uri->base() . $uri->toString(['path', 'query', 'fragment']);
+            } else {
+                $uri->setVar('lang', $this->lang_codes[$lang_code]->sef);
+                $redirectUri = $uri->base() . 'index.php?' . $uri->getQuery();
+            }
+
+            // Set redirect HTTP code to "302 Found".
+            $redirectHttpCode = 302;
+
+            // If selected language is the default language redirect code is "301 Moved Permanently".
+            if ($lang_code === $this->default_lang) {
+                $redirectHttpCode = 301;
+
+                // We cannot cache this redirect in browser. 301 is cacheable by default so we need to force to not cache it in browsers.
+                $this->getApplication()->setHeader('Expires', 'Wed, 17 Aug 2005 00:00:00 GMT', true);
+                $this->getApplication()->setHeader('Last-Modified', gmdate('D, d M Y H:i:s') . ' GMT', true);
+                $this->getApplication()->setHeader('Cache-Control', 'no-store, no-cache, must-revalidate', false);
+                $this->getApplication()->sendHeaders();
+            }
+
+            // Redirect to language.
+            $this->getApplication()->redirect($redirectUri, $redirectHttpCode);
+        }
+
+        // We have found our language and now need to set the cookie and the language value in our system
+        $this->current_lang = $lang_code;
+
+        // Set the request var.
+        $this->getApplication()->getInput()->set('language', $lang_code);
+        $this->getApplication()->set('language', $lang_code);
+        $language = $this->getApplication()->getLanguage();
+
+        if ($language->getTag() !== $lang_code) {
+            $language_new = $this->languageFactory->createLanguage($lang_code, (bool) $this->getApplication()->get('debug_lang'));
+
+            foreach ($language->getPaths() as $extension => $files) {
+                if (strpos($extension, 'plg_system') !== false) {
+                    $extension_name = substr($extension, 11);
+
+                    $language_new->load($extension, JPATH_ADMINISTRATOR)
+                    || $language_new->load($extension, JPATH_PLUGINS . '/system/' . $extension_name);
+
+                    continue;
+                }
+
+                $language_new->load($extension);
+            }
+
+            Factory::$language = $language_new;
+            $this->getApplication()->loadLanguage($language_new);
+        }
+
+        // Create a cookie.
+        if ($this->getLanguageCookie() !== $lang_code) {
+            $this->setLanguageCookie($lang_code);
+        }
+    }
+
+    /**
+     * Reports the privacy related capabilities for this plugin to site administrators.
+     *
+     * @return  array
+     *
+     * @since   3.9.0
+     */
+    public function onPrivacyCollectAdminCapabilities()
+    {
+        $this->loadLanguage();
+
+        return [
+            $this->getApplication()->getLanguage()->_('PLG_SYSTEM_LANGUAGEFILTER') => [
+                $this->getApplication()->getLanguage()->_('PLG_SYSTEM_LANGUAGEFILTER_PRIVACY_CAPABILITY_LANGUAGE_COOKIE'),
+            ],
+        ];
+    }
+
+    /**
+     * Before store user method.
+     *
+     * Method is called before user data is stored in the database.
+     *
+     * @param   array    $user   Holds the old user data.
+     * @param   boolean  $isnew  True if a new user is stored.
+     * @param   array    $new    Holds the new user data.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function onUserBeforeSave($user, $isnew, $new)
+    {
+        if (\array_key_exists('params', $user) && $this->params->get('automatic_change', 1) == 1) {
+            $registry             = new Registry($user['params']);
+            $this->user_lang_code = $registry->get('language');
+
+            if (empty($this->user_lang_code)) {
+                $this->user_lang_code = $this->current_lang;
+            }
+        }
+    }
+
+    /**
+     * After store user method.
+     *
+     * Method is called after user data is stored in the database.
+     *
+     * @param   array    $user     Holds the new user data.
+     * @param   boolean  $isnew    True if a new user is stored.
+     * @param   boolean  $success  True if user was successfully stored in the database.
+     * @param   string   $msg      Message.
+     *
+     * @return  void
+     *
+     * @since   1.6
+     */
+    public function onUserAfterSave($user, $isnew, $success, $msg): void
+    {
+        if ($success && \array_key_exists('params', $user) && $this->params->get('automatic_change', 1) == 1) {
+            $registry  = new Registry($user['params']);
+            $lang_code = $registry->get('language');
+
+            if (empty($lang_code)) {
+                $lang_code = $this->current_lang;
+            }
+
+            if ($lang_code === $this->user_lang_code || !isset($this->lang_codes[$lang_code])) {
+                if ($this->getApplication()->isClient('site')) {
+                    $this->getApplication()->setUserState('com_users.edit.profile.redirect', null);
+                }
+            } else {
+                if ($this->getApplication()->isClient('site')) {
+                    $this->getApplication()->setUserState('com_users.edit.profile.redirect', 'index.php?Itemid='
+                        . $this->getApplication()->getMenu()->getDefault($lang_code)->id . '&lang=' . $this->lang_codes[$lang_code]->sef);
+
+                    // Create a cookie.
+                    $this->setLanguageCookie($lang_code);
+                }
+            }
+        }
+    }
+
+    /**
+     * Method to handle any login logic and report back to the subject.
+     *
+     * @param   array  $user     Holds the user data.
+     * @param   array  $options  Array holding options (remember, autoregister, group).
+     *
+     * @return  null
+     *
+     * @since   1.5
+     */
+    public function onUserLogin($user, $options = [])
+    {
+        if ($this->getApplication()->isClient('site')) {
+            $menu = $this->getApplication()->getMenu();
+
+            if ($this->params->get('automatic_change', 1)) {
+                $assoc     = Associations::isEnabled();
+                $lang_code = $user['language'];
+
+                // If no language is specified for this user, we set it to the site default language
+                if (empty($lang_code)) {
+                    $lang_code = $this->default_lang;
+                }
+
+                // The language has been deleted/disabled or the related content language does not exist/has been unpublished
+                // or the related home page does not exist/has been unpublished
+                if (
+                    !\array_key_exists($lang_code, $this->lang_codes)
+                    || !\array_key_exists($lang_code, Multilanguage::getSiteHomePages())
+                    || !Folder::exists(JPATH_SITE . '/language/' . $lang_code)
+                ) {
+                    $lang_code = $this->current_lang;
+                }
+
+                // Try to get association from the current active menu item
+                $active = $menu->getActive();
+
+                $foundAssociation = false;
+
+                /**
+                 * Looking for associations.
+                 * If the login menu item form contains an internal URL redirection,
+                 * This will override the automatic change to the user preferred site language.
+                 * In that case we use the redirect as defined in the menu item.
+                 *  Otherwise we redirect, when available, to the user preferred site language.
+                 */
+                if ($active && !$active->getParams()->get('login_redirect_url')) {
+                    if ($assoc) {
+                        $associations = MenusHelper::getAssociations($active->id);
+                    }
+
+                    // Retrieves the Itemid from a login form.
+                    $uri = new Uri($this->getApplication()->getUserState('users.login.form.return'));
+
+                    if ($uri->getVar('Itemid')) {
+                        // The login form contains a menu item redirection. Try to get associations from that menu item.
+                        // If any association set to the user preferred site language, redirect to that page.
+                        if ($assoc) {
+                            $associations = MenusHelper::getAssociations($uri->getVar('Itemid'));
+                        }
+
+                        if (isset($associations[$lang_code]) && $menu->getItem($associations[$lang_code])) {
+                            $associationItemid = $associations[$lang_code];
+                            $this->getApplication()->setUserState('users.login.form.return', 'index.php?Itemid=' . $associationItemid);
+                            $foundAssociation = true;
+                        }
+                    } elseif (isset($associations[$lang_code]) && $menu->getItem($associations[$lang_code])) {
+                        /**
+                         * The login form does not contain a menu item redirection.
+                         * The active menu item has associations.
+                         * We redirect to the user preferred site language associated page.
+                         */
+                        $associationItemid = $associations[$lang_code];
+                        $this->getApplication()->setUserState('users.login.form.return', 'index.php?Itemid=' . $associationItemid);
+                        $foundAssociation = true;
+                    } elseif ($active->home) {
+                        // We are on a Home page, we redirect to the user preferred site language Home page.
+                        $item = $menu->getDefault($lang_code);
+
+                        if ($item && $item->language !== $active->language && $item->language !== '*') {
+                            $this->getApplication()->setUserState('users.login.form.return', 'index.php?Itemid=' . $item->id);
+                            $foundAssociation = true;
+                        }
+                    }
+                }
+
+                if ($foundAssociation && $lang_code !== $this->current_lang) {
+                    // Change language.
+                    $this->current_lang = $lang_code;
+
+                    // Create a cookie.
+                    $this->setLanguageCookie($lang_code);
+
+                    // Change the language code.
+                    $this->languageFactory->createLanguage($lang_code);
+                }
+            } else {
+                if ($this->getApplication()->getUserState('users.login.form.return')) {
+                    $this->getApplication()->setUserState('users.login.form.return', Route::_($this->getApplication()->getUserState('users.login.form.return'), false));
+                }
+            }
+        }
+    }
+
+    /**
+     * Method to add alternative meta tags for associated menu items.
+     *
+     * @return  void
+     *
+     * @since   1.7
+     */
+    public function onAfterDispatch()
+    {
+        $doc = $this->getApplication()->getDocument();
+
+        if ($this->getApplication()->isClient('site') && $this->params->get('alternate_meta', 1) && $doc->getType() === 'html') {
+            $languages             = $this->lang_codes;
+            $homes                 = Multilanguage::getSiteHomePages();
+            $menu                  = $this->getApplication()->getMenu();
+            $active                = $menu->getActive();
+            $levels                = $this->getApplication()->getIdentity()->getAuthorisedViewLevels();
+            $remove_default_prefix = $this->params->get('remove_default_prefix', 0);
+            $server                = Uri::getInstance()->toString(['scheme', 'host', 'port']);
+            $is_home               = false;
+
+            // Router can be injected when turned into a DI built plugin
+            $currentInternalUrl    = 'index.php?' . http_build_query($this->getSiteRouter()->getVars());
+
+            if ($active) {
+                $active_link  = Route::_($active->link . '&Itemid=' . $active->id);
+                $current_link = Route::_($currentInternalUrl);
+
+                // Load menu associations
+                if ($active_link === $current_link) {
+                    $associations = MenusHelper::getAssociations($active->id);
+                }
+
+                // Check if we are on the home page
+                $is_home = ($active->home
+                    && ($active_link === $current_link || $active_link === $current_link . 'index.php' || $active_link . '/' === $current_link));
+            }
+
+            // Load component associations.
+            $option = $this->getApplication()->getInput()->get('option');
+
+            $component = $this->getApplication()->bootComponent($option);
+
+            if ($component instanceof AssociationServiceInterface) {
+                $cassociations = $component->getAssociationsExtension()->getAssociationsForItem();
+            } else {
+                $cName = ucfirst(substr($option, 4)) . 'HelperAssociation';
+                \JLoader::register($cName, Path::clean(JPATH_SITE . '/components/' . $option . '/helpers/association.php'));
+
+                if (class_exists($cName) && \is_callable([$cName, 'getAssociations'])) {
+                    $cassociations = \call_user_func([$cName, 'getAssociations']);
+                }
+            }
+
+            // For each language...
+            foreach ($languages as $i => $language) {
+                switch (true) {
+                    // Language without frontend UI || Language without specific home menu || Language without authorized access level
+                    case !\array_key_exists($i, LanguageHelper::getInstalledLanguages(0)):
+                    case !isset($homes[$i]):
+                    case isset($language->access) && $language->access && !\in_array($language->access, $levels):
+                        unset($languages[$i]);
+                        break;
+
+                    // Home page
+                    case $is_home:
+                        $language->link = Route::_('index.php?lang=' . $language->sef . '&Itemid=' . $homes[$i]->id);
+                        break;
+
+                    // Current language link
+                    case $i === $this->current_lang:
+                        $language->link = Route::_($currentInternalUrl);
+                        break;
+
+                    // Component association
+                    case isset($cassociations[$i]):
+                        $language->link = Route::_($cassociations[$i]);
+                        break;
+
+                    // Menu items association
+                    // Heads up! "$item = $menu" here below is an assignment, *NOT* comparison
+                    case isset($associations[$i]) && ($item = $menu->getItem($associations[$i])):
+                        $language->link = Route::_('index.php?Itemid=' . $item->id . '&lang=' . $language->sef);
+                        break;
+
+                    // Too bad...
+                    default:
+                        unset($languages[$i]);
+                }
+            }
+
+            // If there are at least 2 of them, add the rel="alternate" links to the <head>
+            if (\count($languages) > 1) {
+                // Remove the sef from the default language if "Remove URL Language Code" is on
+                if ($remove_default_prefix && isset($languages[$this->default_lang])) {
+                    $languages[$this->default_lang]->link
+                                    = preg_replace('|/' . $languages[$this->default_lang]->sef . '/|', '/', $languages[$this->default_lang]->link, 1);
+                }
+
+                foreach ($languages as $i => $language) {
+                    $doc->addHeadLink($server . $language->link, 'alternate', 'rel', ['hreflang' => $i]);
+                }
+
+                // Add x-default language tag
+                if ($this->params->get('xdefault', 1)) {
+                    $xdefault_language = $this->params->get('xdefault_language', $this->default_lang);
+                    $xdefault_language = ($xdefault_language === 'default') ? $this->default_lang : $xdefault_language;
+
+                    if (isset($languages[$xdefault_language])) {
+                        // Use a custom tag because addHeadLink is limited to one URI per tag
+                        $doc->addCustomTag('<link href="' . $server . $languages[$xdefault_language]->link . '" rel="alternate" hreflang="x-default">');
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Set the language cookie
+     *
+     * @param   string  $languageCode  The language code for which we want to set the cookie
+     *
+     * @return  void
+     *
+     * @since   3.4.2
+     */
+    private function setLanguageCookie($languageCode)
+    {
+        // If is set to use language cookie for a year in plugin params, save the user language in a new cookie.
+        if ((int) $this->params->get('lang_cookie', 0) === 1) {
+            // Create a cookie with one year lifetime.
+            $this->getApplication()->getInput()->cookie->set(
+                ApplicationHelper::getHash('language'),
+                $languageCode,
+                [
+                    'expires'  => time() + 365 * 86400,
+                    'path'     => $this->getApplication()->get('cookie_path', '/'),
+                    'domain'   => $this->getApplication()->get('cookie_domain', ''),
+                    'secure'   => $this->getApplication()->isHttpsForced(),
+                    'httponly' => true,
+                ]
+            );
+        } else {
+            // If not, set the user language in the session (that is already saved in a cookie).
+            $this->getApplication()->getSession()->set('plg_system_languagefilter.language', $languageCode);
+        }
+    }
+
+    /**
+     * Get the language cookie
+     *
+     * @return  string
+     *
+     * @since   3.4.2
+     */
+    private function getLanguageCookie()
+    {
+        // Is is set to use a year language cookie in plugin params, get the user language from the cookie.
+        if ((int) $this->params->get('lang_cookie', 0) === 1) {
+            $languageCode = $this->getApplication()->getInput()->cookie->get(ApplicationHelper::getHash('language'));
+        } else {
+            // Else get the user language from the session.
+            $languageCode = $this->getApplication()->getSession()->get('plg_system_languagefilter.language');
+        }
+
+        // Let's be sure we got a valid language code. Fallback to null.
+        if (!\array_key_exists($languageCode, $this->lang_codes)) {
+            $languageCode = null;
+        }
+
+        return $languageCode;
+    }
+}

plugins/system/log/log.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_log</name>
+	<author>Joomla! Project</author>
+	<creationDate>2007-04</creationDate>
+	<copyright>(C) 2007 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_LOG_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Log</namespace>
+	<files>
+		<folder plugin="log">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_log.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_log.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="log_username"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_LOG_FIELD_LOG_USERNAME_LABEL"
+					default="0"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/log/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.log
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Log\Extension\Log;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Log(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'log')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/log/src/Extension/Log.php

@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.log
+ *
+ * @copyright   (C) 2007 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Log\Extension;
+
+use Joomla\CMS\Authentication\Authentication;
+use Joomla\CMS\Log\Log as Logger;
+use Joomla\CMS\Plugin\CMSPlugin;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! System Logging Plugin.
+ *
+ * @since  1.5
+ */
+final class Log extends CMSPlugin
+{
+    /**
+     * Called if user fails to be logged in.
+     *
+     * @param   array  $response  Array of response data.
+     *
+     * @return  void
+     *
+     * @since   1.5
+     */
+    public function onUserLoginFailure($response)
+    {
+        $errorlog = [];
+
+        switch ($response['status']) {
+            case Authentication::STATUS_SUCCESS:
+                $errorlog['status']  = $response['type'] . ' CANCELED: ';
+                $errorlog['comment'] = $response['error_message'];
+                break;
+
+            case Authentication::STATUS_FAILURE:
+                $errorlog['status']  = $response['type'] . ' FAILURE: ';
+
+                if ($this->params->get('log_username', 0)) {
+                    $errorlog['comment'] = $response['error_message'] . ' ("' . $response['username'] . '")';
+                } else {
+                    $errorlog['comment'] = $response['error_message'];
+                }
+                break;
+
+            default:
+                $errorlog['status']  = $response['type'] . ' UNKNOWN ERROR: ';
+                $errorlog['comment'] = $response['error_message'];
+                break;
+        }
+
+        Logger::addLogger([], Logger::INFO);
+
+        try {
+            Logger::add($errorlog['comment'], Logger::INFO, $errorlog['status']);
+        } catch (\Exception $e) {
+            // If the log file is unwriteable during login then we should not go to the error page
+            return;
+        }
+    }
+}

plugins/system/logout/logout.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_logout</name>
+	<author>Joomla! Project</author>
+	<creationDate>2009-04</creationDate>
+	<copyright>(C) 2009 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SYSTEM_LOGOUT_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Logout</namespace>
+	<files>
+		<folder plugin="logout">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_logout.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_logout.sys.ini</language>
+	</languages>
+</extension>

plugins/system/logout/services/provider.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.logout
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Logout\Extension\Logout;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                return new Logout(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'logout'),
+                    Factory::getApplication()
+                );
+            }
+        );
+    }
+};

plugins/system/logout/src/Extension/Logout.php

@@ -0,0 +1,88 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.logout
+ *
+ * @copyright   (C) 2010 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Logout\Extension;
+
+use Joomla\CMS\Application\ApplicationHelper;
+use Joomla\CMS\Application\CMSApplicationInterface;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\Event\DispatcherInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Plugin class for logout redirect handling.
+ *
+ * @since  1.6
+ */
+final class Logout extends CMSPlugin
+{
+    /**
+     * @param   DispatcherInterface      $dispatcher  The object to observe -- event dispatcher.
+     * @param   array                    $config      An optional associative array of configuration settings.
+     * @param   CMSApplicationInterface  $app         The object to observe -- event dispatcher.
+     *
+     * @since   1.6
+     */
+    public function __construct(DispatcherInterface $dispatcher, array $config, CMSApplicationInterface $app)
+    {
+        parent::__construct($dispatcher, $config);
+
+        $this->setApplication($app);
+
+        // If we are on admin don't process.
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        $hash  = ApplicationHelper::getHash('PlgSystemLogout');
+
+        if ($this->getApplication()->getInput()->cookie->getString($hash)) {
+            // Destroy the cookie.
+            $this->getApplication()->getInput()->cookie->set(
+                $hash,
+                '',
+                1,
+                $this->getApplication()->get('cookie_path', '/'),
+                $this->getApplication()->get('cookie_domain', '')
+            );
+        }
+    }
+
+    /**
+     * Method to handle any logout logic and report back to the subject.
+     *
+     * @param   array  $user     Holds the user data.
+     * @param   array  $options  Array holding options (client, ...).
+     *
+     * @return  boolean  Always returns true.
+     *
+     * @since   1.6
+     */
+    public function onUserLogout($user, $options = [])
+    {
+        if ($this->getApplication()->isClient('site')) {
+            // Create the cookie.
+            $this->getApplication()->getInput()->cookie->set(
+                ApplicationHelper::getHash('PlgSystemLogout'),
+                true,
+                time() + 86400,
+                $this->getApplication()->get('cookie_path', '/'),
+                $this->getApplication()->get('cookie_domain', ''),
+                $this->getApplication()->isHttpsForced(),
+                true
+            );
+        }
+
+        return true;
+    }
+}

plugins/system/privacyconsent/forms/privacyconsent.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fields name="privacyconsent">
+		<fieldset
+			name="privacyconsent"
+			label="PLG_SYSTEM_PRIVACYCONSENT_LABEL"
+		>
+			<field
+				name="privacy"
+				type="privacy"
+				label="PLG_SYSTEM_PRIVACYCONSENT_FIELD_LABEL"
+				default="0"
+				filter="integer"
+				required="true"
+				>
+				<option value="1">PLG_SYSTEM_PRIVACYCONSENT_OPTION_AGREE</option>
+				<option value="0">PLG_SYSTEM_PRIVACYCONSENT_OPTION_DO_NOT_AGREE</option>
+			</field>
+		</fieldset>
+	</fields>
+</form>

plugins/system/privacyconsent/privacyconsent.xml

@@ -0,0 +1,83 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_privacyconsent</name>
+	<author>Joomla! Project</author>
+	<creationDate>2018-04</creationDate>
+	<copyright>(C) 2018 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.9.0</version>
+	<description>PLG_SYSTEM_PRIVACYCONSENT_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\PrivacyConsent</namespace>
+	<files>
+		<folder>forms</folder>
+		<folder plugin="privacyconsent">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_privacyconsent.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_privacyconsent.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic" addfieldprefix="Joomla\Component\Content\Administrator\Field">
+				<field
+					name="privacy_note"
+					type="textarea"
+					label="PLG_SYSTEM_PRIVACYCONSENT_NOTE_FIELD_LABEL"
+					description="PLG_SYSTEM_PRIVACYCONSENT_NOTE_FIELD_DESC"
+					hint="PLG_SYSTEM_PRIVACYCONSENT_NOTE_FIELD_DEFAULT"
+					rows="7"
+					cols="20"
+					filter="html"
+				/>
+				<field
+					name="privacy_type"
+					type="list"
+					label="PLG_SYSTEM_PRIVACYCONSENT_FIELD_TYPE_LABEL"
+					default="article"
+					validate="options"
+					>
+					<option value="article">PLG_SYSTEM_PRIVACYCONSENT_FIELD_TYPE_ARTICLE</option>
+					<option value="menu_item">PLG_SYSTEM_PRIVACYCONSENT_FIELD_TYPE_MENU_ITEM</option>
+				</field>
+				<field
+					name="privacy_article"
+					type="modal_article"
+					label="PLG_SYSTEM_PRIVACYCONSENT_FIELD_ARTICLE_LABEL"
+					description="PLG_SYSTEM_PRIVACYCONSENT_FIELD_ARTICLE_DESC"
+					select="true"
+					new="true"
+					edit="true"
+					clear="true"
+					filter="integer"
+					showon="privacy_type:article"
+				/>
+				<field
+					addfieldprefix="Joomla\Component\Menus\Administrator\Field"
+					name="privacy_menu_item"
+					type="modal_menu"
+					label="PLG_SYSTEM_PRIVACYCONSENT_FIELD_MENU_ITEM_LABEL"
+					select="true"
+					new="true"
+					edit="true"
+					clear="true"
+					filter="integer"
+					showon="privacy_type:menu_item"
+				/>
+				<field
+					name="messageOnRedirect"
+					type="textarea"
+					label="PLG_SYSTEM_PRIVACYCONSENT_REDIRECT_MESSAGE_LABEL"
+					description="PLG_SYSTEM_PRIVACYCONSENT_REDIRECT_MESSAGE_DESC"
+					hint="PLG_SYSTEM_PRIVACYCONSENT_REDIRECT_MESSAGE_DEFAULT"
+					class="span12"
+					rows="7"
+					cols="20"
+					filter="html"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/privacyconsent/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.privacyconsent
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\PrivacyConsent\Extension\PrivacyConsent;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new PrivacyConsent(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'privacyconsent')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/privacyconsent/src/Extension/PrivacyConsent.php

@@ -0,0 +1,445 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.privacyconsent
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\PrivacyConsent\Extension;
+
+use Joomla\CMS\Event\Privacy\CheckPrivacyPolicyPublishedEvent;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Form\Form;
+use Joomla\CMS\Form\FormHelper;
+use Joomla\CMS\Language\Associations;
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\Component\Actionlogs\Administrator\Model\ActionlogModel;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Database\ParameterType;
+use Joomla\Utilities\ArrayHelper;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * An example custom privacyconsent plugin.
+ *
+ * @since  3.9.0
+ */
+final class PrivacyConsent extends CMSPlugin
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * Adds additional fields to the user editing form
+     *
+     * @param   Form   $form  The form to be altered.
+     * @param   mixed  $data  The associated data for the form.
+     *
+     * @return  boolean
+     *
+     * @since   3.9.0
+     */
+    public function onContentPrepareForm(Form $form, $data)
+    {
+        // Check we are manipulating a valid form - we only display this on user registration form and user profile form.
+        $name = $form->getName();
+
+        if (!\in_array($name, ['com_users.profile', 'com_users.registration'])) {
+            return true;
+        }
+
+        // Load plugin language files
+        $this->loadLanguage();
+
+        // We only display this if user has not consented before
+        if (\is_object($data)) {
+            $userId = $data->id ?? 0;
+
+            if ($userId > 0 && $this->isUserConsented($userId)) {
+                return true;
+            }
+        }
+
+        // Add the privacy policy fields to the form.
+        FormHelper::addFieldPrefix('Joomla\\Plugin\\System\\PrivacyConsent\\Field');
+        FormHelper::addFormPath(JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name . '/forms');
+        $form->loadFile('privacyconsent');
+
+        $privacyType = $this->params->get('privacy_type', 'article');
+        $privacyId   = ($privacyType == 'menu_item') ? $this->getPrivacyItemId() : $this->getPrivacyArticleId();
+        $privacynote = $this->params->get('privacy_note');
+
+        // Push the privacy article ID into the privacy field.
+        $form->setFieldAttribute('privacy', $privacyType, $privacyId, 'privacyconsent');
+        $form->setFieldAttribute('privacy', 'note', $privacynote, 'privacyconsent');
+    }
+
+    /**
+     * Method is called before user data is stored in the database
+     *
+     * @param   array    $user   Holds the old user data.
+     * @param   boolean  $isNew  True if a new user is stored.
+     * @param   array    $data   Holds the new user data.
+     *
+     * @return  boolean
+     *
+     * @since   3.9.0
+     * @throws  \InvalidArgumentException on missing required data.
+     */
+    public function onUserBeforeSave($user, $isNew, $data)
+    {
+        // // Only check for front-end user creation/update profile
+        if ($this->getApplication()->isClient('administrator')) {
+            return true;
+        }
+
+        $userId = ArrayHelper::getValue($user, 'id', 0, 'int');
+
+        // Load plugin language files
+        $this->loadLanguage();
+
+        // User already consented before, no need to check it further
+        if ($userId > 0 && $this->isUserConsented($userId)) {
+            return true;
+        }
+
+        // Check that the privacy is checked if required ie only in registration from frontend.
+        $input  = $this->getApplication()->getInput();
+        $option = $input->get('option');
+        $task   = $input->post->get('task');
+        $form   = $input->post->get('jform', [], 'array');
+
+        if (
+            $option == 'com_users' && \in_array($task, ['registration.register', 'profile.save'])
+            && empty($form['privacyconsent']['privacy'])
+        ) {
+            throw new \InvalidArgumentException($this->getApplication()->getLanguage()->_('PLG_SYSTEM_PRIVACYCONSENT_FIELD_ERROR'));
+        }
+
+        return true;
+    }
+
+    /**
+     * Saves user privacy confirmation
+     *
+     * @param   array    $data    entered user data
+     * @param   boolean  $isNew   true if this is a new user
+     * @param   boolean  $result  true if saving the user worked
+     * @param   string   $error   error message
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onUserAfterSave($data, $isNew, $result, $error): void
+    {
+        // Only create an entry on front-end user creation/update profile
+        if ($this->getApplication()->isClient('administrator')) {
+            return;
+        }
+
+        // Get the user's ID
+        $userId = ArrayHelper::getValue($data, 'id', 0, 'int');
+
+        // If user already consented before, no need to check it further
+        if ($userId > 0 && $this->isUserConsented($userId)) {
+            return;
+        }
+
+        $input  = $this->getApplication()->getInput();
+        $option = $input->get('option');
+        $task   = $input->post->get('task');
+        $form   = $input->post->get('jform', [], 'array');
+
+        if (
+            $option == 'com_users'
+            && \in_array($task, ['registration.register', 'profile.save'])
+            && !empty($form['privacyconsent']['privacy'])
+        ) {
+            $userId = ArrayHelper::getValue($data, 'id', 0, 'int');
+
+            // Get the user's IP address
+            $ip = $input->server->get('REMOTE_ADDR', '', 'string');
+
+            // Get the user agent string
+            $userAgent = $input->server->get('HTTP_USER_AGENT', '', 'string');
+
+            // Create the user note
+            $userNote = (object) [
+                'user_id' => $userId,
+                'subject' => 'PLG_SYSTEM_PRIVACYCONSENT_SUBJECT',
+                'body'    => Text::sprintf('PLG_SYSTEM_PRIVACYCONSENT_BODY', $ip, $userAgent),
+                'created' => Factory::getDate()->toSql(),
+            ];
+
+            try {
+                $this->getDatabase()->insertObject('#__privacy_consents', $userNote);
+            } catch (\Exception $e) {
+                // Do nothing if the save fails
+            }
+
+            $userId = ArrayHelper::getValue($data, 'id', 0, 'int');
+
+            $message = [
+                'action'      => 'consent',
+                'id'          => $userId,
+                'title'       => $data['name'],
+                'itemlink'    => 'index.php?option=com_users&task=user.edit&id=' . $userId,
+                'userid'      => $userId,
+                'username'    => $data['username'],
+                'accountlink' => 'index.php?option=com_users&task=user.edit&id=' . $userId,
+            ];
+
+            /** @var ActionlogModel $model */
+            $model = $this->getApplication()->bootComponent('com_actionlogs')->getMVCFactory()->createModel('Actionlog', 'Administrator');
+            $model->addLog([$message], 'PLG_SYSTEM_PRIVACYCONSENT_CONSENT', 'plg_system_privacyconsent', $userId);
+        }
+    }
+
+    /**
+     * Remove all user privacy consent information for the given user ID
+     *
+     * Method is called after user data is deleted from the database
+     *
+     * @param   array    $user     Holds the user data
+     * @param   boolean  $success  True if user was successfully stored in the database
+     * @param   string   $msg      Message
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onUserAfterDelete($user, $success, $msg): void
+    {
+        if (!$success) {
+            return;
+        }
+
+        $userId = ArrayHelper::getValue($user, 'id', 0, 'int');
+
+        if ($userId) {
+            // Remove user's consent
+            $query = $this->getDatabase()->getQuery(true)
+                ->delete($this->getDatabase()->quoteName('#__privacy_consents'))
+                ->where($this->getDatabase()->quoteName('user_id') . ' = :userid')
+                ->bind(':userid', $userId, ParameterType::INTEGER);
+            $this->getDatabase()->setQuery($query);
+            $this->getDatabase()->execute();
+        }
+    }
+
+    /**
+     * If logged in users haven't agreed to privacy consent, redirect them to profile edit page, ask them to agree to
+     * privacy consent before allowing access to any other pages
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onAfterRoute()
+    {
+        // Run this in frontend only
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        $userId = $this->getApplication()->getIdentity()->id;
+
+        // Check to see whether user already consented, if not, redirect to user profile page
+        if ($userId > 0) {
+            // Load plugin language files
+            $this->loadLanguage();
+
+            // If user consented before, no need to check it further
+            if ($this->isUserConsented($userId)) {
+                return;
+            }
+
+            $input  = $this->getApplication()->getInput();
+            $option = $input->getCmd('option');
+            $task   = $input->get('task', '');
+            $view   = $input->getString('view', '');
+            $layout = $input->getString('layout', '');
+            $id     = $input->getInt('id');
+
+            $privacyArticleId = $this->getPrivacyArticleId();
+
+            /*
+             * If user is already on edit profile screen or view privacy article
+             * or press update/apply button, or logout, do nothing to avoid infinite redirect
+             */
+            $allowedUserTasks = [
+                'profile.save', 'profile.apply', 'user.logout', 'user.menulogout',
+                'method', 'methods', 'captive', 'callback',
+            ];
+            $isAllowedUserTask = \in_array($task, $allowedUserTasks)
+                || substr($task, 0, 8) === 'captive.'
+                || substr($task, 0, 8) === 'methods.'
+                || substr($task, 0, 7) === 'method.'
+                || substr($task, 0, 9) === 'callback.';
+
+            if (
+                ($option == 'com_users' && $isAllowedUserTask)
+                || ($option == 'com_content' && $view == 'article' && $id == $privacyArticleId)
+                || ($option == 'com_users' && $view == 'profile' && $layout == 'edit')
+            ) {
+                return;
+            }
+
+            // Redirect to com_users profile edit
+            $this->getApplication()->enqueueMessage($this->getRedirectMessage(), 'notice');
+            $link = 'index.php?option=com_users&view=profile&layout=edit';
+            $this->getApplication()->redirect(Route::_($link, false));
+        }
+    }
+
+    /**
+     * Event to specify whether a privacy policy has been published.
+     *
+     * @param   CheckPrivacyPolicyPublishedEvent  $event  The privacy policy status event.
+     *
+     * @return  void
+     *
+     * @since   3.9.0
+     */
+    public function onPrivacyCheckPrivacyPolicyPublished(CheckPrivacyPolicyPublishedEvent $event)
+    {
+        // Data, with keys "published", "editLink" and "articlePublished".
+        $policy = $event->getPolicyInfo();
+
+        // If another plugin has already indicated a policy is published, we won't change anything here
+        if ($policy['published']) {
+            return;
+        }
+
+        $articleId = (int) $this->params->get('privacy_article');
+
+        if (!$articleId) {
+            return;
+        }
+
+        // Check if the article exists in database and is published
+        $query = $this->getDatabase()->getQuery(true)
+            ->select($this->getDatabase()->quoteName(['id', 'state']))
+            ->from($this->getDatabase()->quoteName('#__content'))
+            ->where($this->getDatabase()->quoteName('id') . ' = :id')
+            ->bind(':id', $articleId, ParameterType::INTEGER);
+        $this->getDatabase()->setQuery($query);
+
+        $article = $this->getDatabase()->loadObject();
+
+        // Check if the article exists
+        if (!$article) {
+            return;
+        }
+
+        // Check if the article is published
+        if ($article->state == 1) {
+            $policy['articlePublished'] = true;
+        }
+
+        $policy['published'] = true;
+        $policy['editLink']  = Route::_('index.php?option=com_content&task=article.edit&id=' . $articleId);
+
+        $event->updatePolicyInfo($policy);
+    }
+
+    /**
+     * Returns the configured redirect message and falls back to the default version.
+     *
+     * @return  string  redirect message
+     *
+     * @since   3.9.0
+     */
+    private function getRedirectMessage()
+    {
+        $messageOnRedirect = trim($this->params->get('messageOnRedirect', ''));
+
+        if (empty($messageOnRedirect)) {
+            return $this->getApplication()->getLanguage()->_('PLG_SYSTEM_PRIVACYCONSENT_REDIRECT_MESSAGE_DEFAULT');
+        }
+
+        return $messageOnRedirect;
+    }
+
+    /**
+     * Method to check if the given user has consented yet
+     *
+     * @param   integer  $userId  ID of uer to check
+     *
+     * @return  boolean
+     *
+     * @since   3.9.0
+     */
+    private function isUserConsented($userId)
+    {
+        $userId = (int) $userId;
+        $db     = $this->getDatabase();
+        $query  = $db->getQuery(true);
+
+        $query->select('COUNT(*)')
+            ->from($db->quoteName('#__privacy_consents'))
+            ->where($db->quoteName('user_id') . ' = :userid')
+            ->where($db->quoteName('subject') . ' = ' . $db->quote('PLG_SYSTEM_PRIVACYCONSENT_SUBJECT'))
+            ->where($db->quoteName('state') . ' = 1')
+            ->bind(':userid', $userId, ParameterType::INTEGER);
+        $db->setQuery($query);
+
+        return (int) $db->loadResult() > 0;
+    }
+
+    /**
+     * Get privacy article ID. If the site is a multilingual website and there is associated article for the
+     * current language, ID of the associated article will be returned
+     *
+     * @return  integer
+     *
+     * @since   3.9.0
+     */
+    private function getPrivacyArticleId()
+    {
+        $privacyArticleId = $this->params->get('privacy_article');
+
+        if ($privacyArticleId > 0 && Associations::isEnabled()) {
+            $privacyAssociated = Associations::getAssociations('com_content', '#__content', 'com_content.item', $privacyArticleId);
+            $currentLang       = $this->getApplication()->getLanguage()->getTag();
+
+            if (isset($privacyAssociated[$currentLang])) {
+                $privacyArticleId = $privacyAssociated[$currentLang]->id;
+            }
+        }
+
+        return $privacyArticleId;
+    }
+
+    /**
+     * Get privacy menu item ID. If the site is a multilingual website and there is associated menu item for the
+     * current language, ID of the associated menu item will be returned.
+     *
+     * @return  integer
+     *
+     * @since   4.0.0
+     */
+    private function getPrivacyItemId()
+    {
+        $itemId = $this->params->get('privacy_menu_item');
+
+        if ($itemId > 0 && Associations::isEnabled()) {
+            $privacyAssociated = Associations::getAssociations('com_menus', '#__menu', 'com_menus.item', $itemId, 'id', '', '');
+            $currentLang       = $this->getApplication()->getLanguage()->getTag();
+
+            if (isset($privacyAssociated[$currentLang])) {
+                $itemId = $privacyAssociated[$currentLang]->id;
+            }
+        }
+
+        return $itemId;
+    }
+}

plugins/system/privacyconsent/src/Field/PrivacyField.php

@@ -0,0 +1,133 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.privacyconsent
+ *
+ * @copyright   (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\PrivacyConsent\Field;
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\Form\Field\RadioField;
+use Joomla\CMS\Language\Multilanguage;
+use Joomla\CMS\Language\Text;
+use Joomla\Component\Content\Site\Helper\RouteHelper;
+use Joomla\Database\ParameterType;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Provides input for privacy
+ *
+ * @since  3.9.0
+ */
+class PrivacyField extends RadioField
+{
+    /**
+     * The form field type.
+     *
+     * @var    string
+     * @since  3.9.0
+     */
+    protected $type = 'privacy';
+
+    /**
+     * Method to get the field input markup.
+     *
+     * @return  string   The field input markup.
+     *
+     * @since   3.9.0
+     */
+    protected function getInput()
+    {
+        // Display the message before the field
+        echo $this->getRenderer('plugins.system.privacyconsent.message')->render($this->getLayoutData());
+
+        return parent::getInput();
+    }
+
+    /**
+     * Method to get the field label markup.
+     *
+     * @return  string  The field label markup.
+     *
+     * @since   3.9.0
+     */
+    protected function getLabel()
+    {
+        if ($this->hidden) {
+            return '';
+        }
+
+        return $this->getRenderer('plugins.system.privacyconsent.label')->render($this->getLayoutData());
+    }
+
+    /**
+     * Method to get the data to be passed to the layout for rendering.
+     *
+     * @return  array
+     *
+     * @since   3.9.4
+     */
+    protected function getLayoutData()
+    {
+        $data = parent::getLayoutData();
+
+        $article        = false;
+        $link           = false;
+        $privacyArticle = $this->element['article'] > 0 ? (int) $this->element['article'] : 0;
+
+        if ($privacyArticle && Factory::getApplication()->isClient('site')) {
+            $db    = $this->getDatabase();
+            $query = $db->getQuery(true)
+                ->select($db->quoteName(['id', 'alias', 'catid', 'language']))
+                ->from($db->quoteName('#__content'))
+                ->where($db->quoteName('id') . ' = :id')
+                ->bind(':id', $privacyArticle, ParameterType::INTEGER);
+            $db->setQuery($query);
+            $article = $db->loadObject();
+
+            $slug           = $article->alias ? ($article->id . ':' . $article->alias) : $article->id;
+            $article->link  = RouteHelper::getArticleRoute($slug, $article->catid, $article->language);
+            $link           = $article->link;
+        }
+
+        $privacyMenuItem = $this->element['menu_item'] > 0 ? (int) $this->element['menu_item'] : 0;
+
+        if ($privacyMenuItem && Factory::getApplication()->isClient('site')) {
+            $link = 'index.php?Itemid=' . $privacyMenuItem;
+
+            if (Multilanguage::isEnabled()) {
+                $db    = $this->getDatabase();
+                $query = $db->getQuery(true)
+                    ->select($db->quoteName(['id', 'language']))
+                    ->from($db->quoteName('#__menu'))
+                    ->where($db->quoteName('id') . ' = :id')
+                    ->bind(':id', $privacyMenuItem, ParameterType::INTEGER);
+                $db->setQuery($query);
+                $menuItem = $db->loadObject();
+
+                $link .= '&lang=' . $menuItem->language;
+            }
+        }
+
+        $extraData = [
+            'privacynote'          => !empty($this->element['note']) ? $this->element['note'] : Text::_('PLG_SYSTEM_PRIVACYCONSENT_NOTE_FIELD_DEFAULT'),
+            'options'              => $this->getOptions(),
+            'value'                => (string) $this->value,
+            'translateLabel'       => $this->translateLabel,
+            'translateDescription' => $this->translateDescription,
+            'translateHint'        => $this->translateHint,
+            'privacyArticle'       => $privacyArticle,
+            'article'              => $article,
+            'privacyLink'          => $link,
+        ];
+
+        return array_merge($data, $extraData);
+    }
+}

plugins/system/redirect/form/excludes.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fieldset>
+		<field
+			name="term"
+			type="text"
+			label="PLG_SYSTEM_REDIRECT_FIELD_EXCLUDE_URLS_TERM_LABEL"
+			description="PLG_SYSTEM_REDIRECT_FIELD_EXCLUDE_URLS_TERM_DESC"
+			required="true"
+		/>
+		<field
+			name="regexp"
+			type="checkbox"
+			label="PLG_SYSTEM_REDIRECT_FIELD_EXCLUDE_URLS_REGEXP_LABEL"
+			filter="integer"
+		/>
+	</fieldset>
+</form>

plugins/system/redirect/redirect.xml

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_redirect</name>
+	<author>Joomla! Project</author>
+	<creationDate>2009-04</creationDate>
+	<copyright>(C) 2009 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SYSTEM_REDIRECT_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Redirect</namespace>
+	<files>
+		<folder>form</folder>
+		<folder plugin="redirect">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_redirect.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_redirect.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="collect_urls"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_REDIRECT_FIELD_COLLECT_URLS_LABEL"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="includeUrl"
+					type="radio"
+					layout="joomla.form.field.radio.switcher"
+					label="PLG_SYSTEM_REDIRECT_FIELD_STORE_FULL_URL_LABEL"
+					default="1"
+					filter="integer"
+					>
+					<option value="0">JNO</option>
+					<option value="1">JYES</option>
+				</field>
+				<field
+					name="exclude_urls"
+					type="subform"
+					label="PLG_SYSTEM_REDIRECT_FIELD_EXCLUDE_URLS_LABEL"
+					multiple="true"
+					formsource="plugins/system/redirect/form/excludes.xml"
+					layout="joomla.form.field.subform.repeatable-table"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/redirect/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.redirect
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Redirect\Extension\Redirect;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Redirect(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'redirect')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/redirect/src/Extension/Redirect.php

@@ -0,0 +1,265 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.redirect
+ *
+ * @copyright   (C) 2009 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Redirect\Extension;
+
+use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Event\ErrorEvent;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Database\ParameterType;
+use Joomla\Event\SubscriberInterface;
+use Joomla\String\StringHelper;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Plugin class for redirect handling.
+ *
+ * @since  1.6
+ */
+final class Redirect extends CMSPlugin implements SubscriberInterface
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return  array
+     *
+     * @since   4.0.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return ['onError' => 'handleError'];
+    }
+
+    /**
+     * Internal processor for all error handlers
+     *
+     * @param   ErrorEvent  $event  The event object
+     *
+     * @return  void
+     *
+     * @since   3.5
+     */
+    public function handleError(ErrorEvent $event)
+    {
+        /** @var \Joomla\CMS\Application\CMSApplication $app */
+        $app = $event->getApplication();
+
+        if ($app->isClient('administrator') || ((int) $event->getError()->getCode() !== 404)) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        $uri = Uri::getInstance();
+
+        // These are the original URLs
+        $orgurl                = rawurldecode($uri->toString(['scheme', 'host', 'port', 'path', 'query', 'fragment']));
+        $orgurlRel             = rawurldecode($uri->toString(['path', 'query', 'fragment']));
+
+        // The above doesn't work for sub directories, so do this
+        $orgurlRootRel         = str_replace(Uri::root(), '', $orgurl);
+
+        // For when users have added / to the url
+        $orgurlRootRelSlash    = str_replace(Uri::root(), '/', $orgurl);
+        $orgurlWithoutQuery    = rawurldecode($uri->toString(['scheme', 'host', 'port', 'path', 'fragment']));
+        $orgurlRelWithoutQuery = rawurldecode($uri->toString(['path', 'fragment']));
+
+        // These are the URLs we save and use
+        $url                = StringHelper::strtolower(rawurldecode($uri->toString(['scheme', 'host', 'port', 'path', 'query', 'fragment'])));
+        $urlRel             = StringHelper::strtolower(rawurldecode($uri->toString(['path', 'query', 'fragment'])));
+
+        // The above doesn't work for sub directories, so do this
+        $urlRootRel         = str_replace(Uri::root(), '', $url);
+
+        // For when users have added / to the url
+        $urlRootRelSlash    = str_replace(Uri::root(), '/', $url);
+        $urlWithoutQuery    = StringHelper::strtolower(rawurldecode($uri->toString(['scheme', 'host', 'port', 'path', 'fragment'])));
+        $urlRelWithoutQuery = StringHelper::strtolower(rawurldecode($uri->toString(['path', 'fragment'])));
+
+        $excludes = (array) $this->params->get('exclude_urls');
+
+        $skipUrl = false;
+
+        foreach ($excludes as $exclude) {
+            if (empty($exclude->term)) {
+                continue;
+            }
+
+            if (!empty($exclude->regexp)) {
+                // Only check $url, because it includes all other sub urls
+                if (preg_match('/' . $exclude->term . '/i', $orgurlRel)) {
+                    $skipUrl = true;
+                    break;
+                }
+            } else {
+                if (StringHelper::strpos($orgurlRel, $exclude->term) !== false) {
+                    $skipUrl = true;
+                    break;
+                }
+            }
+        }
+
+        /**
+         * Why is this (still) here?
+         * Because hackers still try urls with mosConfig_* and Url Injection with =http[s]:// and we dont want to log/redirect these requests
+         */
+        if ($skipUrl || (strpos($url, 'mosConfig_') !== false) || (strpos($url, '=http') !== false)) {
+            return;
+        }
+
+        $query = $this->getDatabase()->getQuery(true);
+
+        $query->select('*')
+            ->from($this->getDatabase()->quoteName('#__redirect_links'))
+            ->whereIn(
+                $this->getDatabase()->quoteName('old_url'),
+                [
+                    $url,
+                    $urlRel,
+                    $urlRootRel,
+                    $urlRootRelSlash,
+                    $urlWithoutQuery,
+                    $urlRelWithoutQuery,
+                    $orgurl,
+                    $orgurlRel,
+                    $orgurlRootRel,
+                    $orgurlRootRelSlash,
+                    $orgurlWithoutQuery,
+                    $orgurlRelWithoutQuery,
+                ],
+                ParameterType::STRING
+            );
+
+        $this->getDatabase()->setQuery($query);
+
+        $redirect = null;
+
+        try {
+            $redirects = $this->getDatabase()->loadAssocList();
+        } catch (\Exception $e) {
+            $event->setError(new \Exception($this->getApplication()->getLanguage()->_('PLG_SYSTEM_REDIRECT_ERROR_UPDATING_DATABASE'), 500, $e));
+
+            return;
+        }
+
+        $possibleMatches = array_unique(
+            [
+                $url,
+                $urlRel,
+                $urlRootRel,
+                $urlRootRelSlash,
+                $urlWithoutQuery,
+                $urlRelWithoutQuery,
+                $orgurl,
+                $orgurlRel,
+                $orgurlRootRel,
+                $orgurlRootRelSlash,
+                $orgurlWithoutQuery,
+                $orgurlRelWithoutQuery,
+            ]
+        );
+
+        foreach ($possibleMatches as $match) {
+            if (($index = array_search($match, array_column($redirects, 'old_url'))) !== false) {
+                $redirect = (object) $redirects[$index];
+
+                if ((int) $redirect->published === 1) {
+                    break;
+                }
+            }
+        }
+
+        // A redirect object was found and, if published, will be used
+        if ($redirect !== null && ((int) $redirect->published === 1)) {
+            if (!$redirect->header || (bool) ComponentHelper::getParams('com_redirect')->get('mode', false) === false) {
+                $redirect->header = 301;
+            }
+
+            if ($redirect->header < 400 && $redirect->header >= 300) {
+                $urlQuery = $uri->getQuery();
+
+                $oldUrlParts = parse_url($redirect->old_url);
+
+                $newUrl = $redirect->new_url;
+
+                if ($urlQuery !== '' && empty($oldUrlParts['query'])) {
+                    $newUrl .= '?' . $urlQuery;
+                }
+
+                $dest = Uri::isInternal($newUrl) || strpos($newUrl, 'http') === false ?
+                    Route::_($newUrl) : $newUrl;
+
+                // In case the url contains double // lets remove it
+                $destination = str_replace(Uri::root() . '/', Uri::root(), $dest);
+
+                // Always count redirect hits
+                $redirect->hits++;
+
+                try {
+                    $this->getDatabase()->updateObject('#__redirect_links', $redirect, 'id');
+                } catch (\Exception $e) {
+                    // We don't log issues for now
+                }
+
+                $app->redirect($destination, (int) $redirect->header);
+            }
+
+            $event->setError(new \RuntimeException($event->getError()->getMessage(), $redirect->header, $event->getError()));
+        } elseif ($redirect === null) {
+            // No redirect object was found so we create an entry in the redirect table
+            if ((bool) $this->params->get('collect_urls', 1)) {
+                if (!$this->params->get('includeUrl', 1)) {
+                    $url = $urlRel;
+                }
+
+                $nowDate = Factory::getDate()->toSql();
+
+                $data = (object) [
+                    'id'            => 0,
+                    'old_url'       => $url,
+                    'referer'       => $app->getInput()->server->getString('HTTP_REFERER', ''),
+                    'hits'          => 1,
+                    'published'     => 0,
+                    'created_date'  => $nowDate,
+                    'modified_date' => $nowDate,
+                ];
+
+                try {
+                    $this->getDatabase()->insertObject('#__redirect_links', $data, 'id');
+                } catch (\Exception $e) {
+                    $event->setError(new \Exception($this->getApplication()->getLanguage()->_('PLG_SYSTEM_REDIRECT_ERROR_UPDATING_DATABASE'), 500, $e));
+
+                    return;
+                }
+            }
+        } else {
+            // We have an unpublished redirect object, increment the hit counter
+            $redirect->hits++;
+
+            try {
+                $this->getDatabase()->updateObject('#__redirect_links', $redirect, ['id']);
+            } catch (\Exception $e) {
+                $event->setError(new \Exception($this->getApplication()->getLanguage()->_('PLG_SYSTEM_REDIRECT_ERROR_UPDATING_DATABASE'), 500, $e));
+
+                return;
+            }
+        }
+    }
+}

plugins/system/remember/remember.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_remember</name>
+	<author>Joomla! Project</author>
+	<creationDate>2007-04</creationDate>
+	<copyright>(C) 2007 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_REMEMBER_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Remember</namespace>
+	<files>
+		<folder plugin="remember">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_remember.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_remember.sys.ini</language>
+	</languages>
+</extension>

plugins/system/remember/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.remember
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Remember\Extension\Remember;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Remember(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'remember')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/remember/src/Extension/Remember.php

@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.remember
+ *
+ * @copyright   (C) 2007 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Remember\Extension;
+
+use Joomla\CMS\Log\Log;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserHelper;
+use Joomla\Database\DatabaseAwareTrait;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! System Remember Me Plugin
+ *
+ * @since  1.5
+ */
+final class Remember extends CMSPlugin
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * Remember me method to run onAfterInitialise
+     * Only purpose is to initialise the login authentication process if a cookie is present
+     *
+     * @return  void
+     *
+     * @since   1.5
+     *
+     * @throws  InvalidArgumentException
+     */
+    public function onAfterInitialise()
+    {
+        // No remember me for admin.
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        // Check for a cookie if user is not logged in
+        if ($this->getApplication()->getIdentity()->guest) {
+            $cookieName = 'joomla_remember_me_' . UserHelper::getShortHashedUserAgent();
+
+            // Check for the cookie
+            if ($this->getApplication()->getInput()->cookie->get($cookieName)) {
+                $this->getApplication()->login(['username' => ''], ['silent' => true]);
+            }
+        }
+    }
+
+    /**
+     * Imports the authentication plugin on user logout to make sure that the cookie is destroyed.
+     *
+     * @param   array  $user     Holds the user data.
+     * @param   array  $options  Array holding options (remember, autoregister, group).
+     *
+     * @return  boolean
+     */
+    public function onUserLogout($user, $options)
+    {
+        // No remember me for admin
+        if (!$this->getApplication()->isClient('site')) {
+            return true;
+        }
+
+        $cookieName = 'joomla_remember_me_' . UserHelper::getShortHashedUserAgent();
+
+        // Check for the cookie
+        if ($this->getApplication()->getInput()->cookie->get($cookieName)) {
+            // Make sure authentication group is loaded to process onUserAfterLogout event
+            PluginHelper::importPlugin('authentication');
+        }
+
+        return true;
+    }
+
+    /**
+     * Method is called before user data is stored in the database
+     * Invalidate all existing remember-me cookies after a password change
+     *
+     * @param   array    $user   Holds the old user data.
+     * @param   boolean  $isnew  True if a new user is stored.
+     * @param   array    $data   Holds the new user data.
+     *
+     * @return  boolean
+     *
+     * @since   3.8.6
+     */
+    public function onUserBeforeSave($user, $isnew, $data)
+    {
+        // Irrelevant on new users
+        if ($isnew) {
+            return true;
+        }
+
+        // Irrelevant, because password was not changed by user
+        if (empty($data['password_clear'])) {
+            return true;
+        }
+
+        // But now, we need to do something - Delete all tokens for this user!
+        $db    = $this->getDatabase();
+        $query = $db->getQuery(true)
+            ->delete($db->quoteName('#__user_keys'))
+            ->where($db->quoteName('user_id') . ' = :userid')
+            ->bind(':userid', $user['username']);
+
+        try {
+            $db->setQuery($query)->execute();
+        } catch (\RuntimeException $e) {
+            // Log an alert for the site admin
+            Log::add(
+                sprintf('Failed to delete cookie token for user %s with the following error: %s', $user['username'], $e->getMessage()),
+                Log::WARNING,
+                'security'
+            );
+        }
+
+        return true;
+    }
+}

plugins/system/schedulerunner/schedulerunner.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_schedulerunner</name>
+	<author>Joomla! Project</author>
+	<creationDate>2021-08</creationDate>
+	<copyright>(C) 2021 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.1</version>
+	<description>PLG_SYSTEM_SCHEDULERUNNER_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\ScheduleRunner</namespace>
+	<media destination="plg_system_schedulerunner" folder="media">
+		<folder>js</folder>
+		<filename>joomla.asset.json</filename>
+	</media>
+	<files>
+		<folder plugin="schedulerunner">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_schedulerunner.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_schedulerunner.sys.ini</language>
+	</languages>
+</extension>

plugins/system/schedulerunner/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.schedulerunner
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\ScheduleRunner\Extension\ScheduleRunner;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new ScheduleRunner(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'schedulerunner')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/schedulerunner/src/Extension/ScheduleRunner.php

@@ -0,0 +1,357 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.schedulerunner
+ *
+ * @copyright   (C) 2021 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\ScheduleRunner\Extension;
+
+use Joomla\CMS\Component\ComponentHelper;
+use Joomla\CMS\Event\Model;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Log\Log;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Session\Session;
+use Joomla\CMS\Table\Extension;
+use Joomla\CMS\User\UserHelper;
+use Joomla\Component\Scheduler\Administrator\Model\TasksModel;
+use Joomla\Component\Scheduler\Administrator\Scheduler\Scheduler;
+use Joomla\Component\Scheduler\Administrator\Task\Task;
+use Joomla\Event\Event;
+use Joomla\Event\EventInterface;
+use Joomla\Event\SubscriberInterface;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * This plugin implements listeners to support a visitor-triggered lazy-scheduling pattern.
+ * If `com_scheduler` is installed/enabled and its configuration allows unprotected lazy scheduling, this plugin
+ * injects into each response with an HTML context a JS file {@see PlgSystemScheduleRunner::injectScheduleRunner()} that
+ * sets up an AJAX callback to trigger the scheduler {@see PlgSystemScheduleRunner::runScheduler()}. This is achieved
+ * through a call to the `com_ajax` component.
+ * Also supports the scheduler component configuration form through auto-generation of the webcron key and injection
+ * of JS of usability enhancement.
+ *
+ * @since 4.1.0
+ */
+final class ScheduleRunner extends CMSPlugin implements SubscriberInterface
+{
+    /**
+     * Length of auto-generated webcron key.
+     *
+     * @var integer
+     * @since 4.1.0
+     */
+    private const WEBCRON_KEY_LENGTH = 20;
+
+    /**
+     * @inheritDoc
+     *
+     * @return string[]
+     *
+     * @since 4.1.0
+     *
+     * @throws \Exception
+     */
+    public static function getSubscribedEvents(): array
+    {
+        $config = ComponentHelper::getParams('com_scheduler');
+        $app    = Factory::getApplication();
+
+        $mapping  = [];
+
+        if ($app->isClient('site') || $app->isClient('administrator')) {
+            $mapping['onBeforeCompileHead']    = 'injectLazyJS';
+            $mapping['onAjaxRunSchedulerLazy'] = 'runLazyCron';
+
+            // Only allowed in the frontend
+            if ($app->isClient('site')) {
+                if ($config->get('webcron.enabled')) {
+                    $mapping['onAjaxRunSchedulerWebcron'] = 'runWebCron';
+                }
+            } elseif ($app->isClient('administrator')) {
+                $mapping['onContentPrepareForm']  = 'enhanceSchedulerConfig';
+                $mapping['onExtensionBeforeSave'] = 'generateWebcronKey';
+
+                $mapping['onAjaxRunSchedulerTest'] = 'runTestCron';
+            }
+        }
+
+        return $mapping;
+    }
+
+    /**
+     * Inject JavaScript to trigger the scheduler in HTML contexts.
+     *
+     * @param   EventInterface  $event  The onBeforeCompileHead event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     */
+    public function injectLazyJS(EventInterface $event): void
+    {
+        // Only inject in HTML documents
+        if ($this->getApplication()->getDocument()->getType() !== 'html') {
+            return;
+        }
+
+        $config = ComponentHelper::getParams('com_scheduler');
+
+        if (!$config->get('lazy_scheduler.enabled', true)) {
+            return;
+        }
+
+        /** @var TasksModel $model */
+        $model = $this->getApplication()->bootComponent('com_scheduler')
+            ->getMVCFactory()->createModel('Tasks', 'Administrator', ['ignore_request' => true]);
+
+        $now = Factory::getDate('now', 'UTC');
+
+        if (!$model->hasDueTasks($now)) {
+            return;
+        }
+
+        // Add configuration options
+        $triggerInterval = $config->get('lazy_scheduler.interval', 300);
+        $this->getApplication()->getDocument()->addScriptOptions('plg_system_schedulerunner', ['interval' => $triggerInterval]);
+
+        // Load and injection directive
+        $wa = $this->getApplication()->getDocument()->getWebAssetManager();
+        $wa->getRegistry()->addExtensionRegistryFile('plg_system_schedulerunner');
+        $wa->useScript('plg_system_schedulerunner.run-schedule');
+    }
+
+    /**
+     * Acts on the LazyCron trigger from the frontend when Lazy Cron is enabled in the Scheduler component
+     * configuration. The lazy cron trigger is implemented in client-side JavaScript which is injected on every page
+     * load with an HTML context when the component configuration allows it. This method then triggers the Scheduler,
+     * which effectively runs the next Task in the Scheduler's task queue.
+     *
+     * @param   EventInterface  $e  The onAjaxRunSchedulerLazy event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     *
+     * @throws \Exception
+     */
+    public function runLazyCron(EventInterface $e)
+    {
+        $config = ComponentHelper::getParams('com_scheduler');
+
+        if (!$config->get('lazy_scheduler.enabled', true)) {
+            return;
+        }
+
+        // Since the the request from the frontend may time out, try allowing execution after disconnect.
+        if (\function_exists('ignore_user_abort')) {
+            ignore_user_abort(true);
+        }
+
+        // Prevent PHP from trying to output to the user pipe. PHP may kill the script otherwise if the pipe is not accessible.
+        ob_start();
+
+        // Suppress all errors to avoid any output
+        try {
+            $this->runScheduler();
+        } catch (\Exception $e) {
+        }
+
+        ob_end_clean();
+    }
+
+    /**
+     * This method is responsible for the WebCron functionality of the Scheduler component.<br/>
+     * Acting on a `com_ajax` call, this method can work in two ways:
+     * 1. If no Task ID is specified, it triggers the Scheduler to run the next task in
+     *   the task queue.
+     * 2. If a Task ID is specified, it fetches the task (if it exists) from the Scheduler API and executes it.<br/>
+     *
+     * URL query parameters:
+     * - `hash` string (required)   Webcron hash (from the Scheduler component configuration).
+     * - `id`   int (optional)      ID of the task to trigger.
+     *
+     * @param   Event  $event  The onAjaxRunSchedulerWebcron event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     *
+     * @throws \Exception
+     */
+    public function runWebCron(Event $event)
+    {
+        $config = ComponentHelper::getParams('com_scheduler');
+        $hash   = $config->get('webcron.key', '');
+
+        if (!$config->get('webcron.enabled', false)) {
+            Log::add($this->getApplication()->getLanguage()->_('PLG_SYSTEM_SCHEDULE_RUNNER_WEBCRON_DISABLED'));
+            throw new \Exception($this->getApplication()->getLanguage()->_('JERROR_ALERTNOAUTHOR'), 403);
+        }
+
+        if (!\strlen($hash) || $hash !== $this->getApplication()->getInput()->get('hash')) {
+            throw new \Exception($this->getApplication()->getLanguage()->_('JERROR_ALERTNOAUTHOR'), 403);
+        }
+
+        $id = (int) $this->getApplication()->getInput()->getInt('id', 0);
+
+        $task = $this->runScheduler($id);
+
+        if (!empty($task) && !empty($task->getContent()['exception'])) {
+            throw $task->getContent()['exception'];
+        }
+    }
+
+    /**
+     * This method is responsible for the "test run" functionality in the Scheduler administrator backend interface.
+     * Acting on a `com_ajax` call, this method requires the URL to have a `id` query parameter (corresponding to an
+     * existing Task ID).
+     *
+     * @param   Event  $event  The onAjaxRunScheduler event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     *
+     * @throws \Exception
+     */
+    public function runTestCron(Event $event)
+    {
+        if (!Session::checkToken('GET')) {
+            return;
+        }
+
+        $id              = (int) $this->getApplication()->getInput()->getInt('id');
+        $allowConcurrent = $this->getApplication()->getInput()->getBool('allowConcurrent', false);
+
+        $user = $this->getApplication()->getIdentity();
+
+        if (empty($id) || !$user->authorise('core.testrun', 'com_scheduler.task.' . $id)) {
+            throw new \Exception($this->getApplication()->getLanguage()->_('JERROR_ALERTNOAUTHOR'), 403);
+        }
+
+        /**
+         * ?: About allow simultaneous, how do we detect if it failed because of pre-existing lock?
+         *
+         * We will allow CLI exclusive tasks to be fetched and executed, it's left to routines to do a runtime check
+         * if they want to refuse normal operation.
+         */
+        $task = (new Scheduler())->getTask(
+            [
+                'id'               => $id,
+                'allowDisabled'    => true,
+                'bypassScheduling' => true,
+                'allowConcurrent'  => $allowConcurrent,
+            ]
+        );
+
+        if ($task) {
+            $task->run();
+            $event->addArgument('result', $task->getContent());
+        } else {
+            /**
+             * Placeholder result, but the idea is if we failed to fetch the task, it's likely because another task was
+             * already running. This is a fair assumption if this test run was triggered through the administrator backend,
+             * so we know the task probably exists and is either enabled/disabled (not trashed).
+             */
+            // @todo language constant + review if this is done right.
+            $event->addArgument('result', ['message' => 'could not acquire lock on task. retry or allow concurrency.']);
+        }
+    }
+
+    /**
+     * Run the scheduler, allowing execution of a single due task.
+     * Does not bypass task scheduling, meaning that even if an ID is passed the task is only
+     * triggered if it is due.
+     *
+     * @param   integer  $id  The optional ID of the task to run
+     *
+     * @return ?Task
+     *
+     * @since 4.1.0
+     * @throws \RuntimeException
+     */
+    private function runScheduler(int $id = 0): ?Task
+    {
+        return (new Scheduler())->runTask(['id' => $id]);
+    }
+
+    /**
+     * Enhance the scheduler config form by dynamically populating or removing display fields.
+     *
+     * @param   Model\PrepareFormEvent  $event  The onContentPrepareForm event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \UnexpectedValueException|\RuntimeException
+     *
+     * @todo  Move to another plugin?
+     */
+    public function enhanceSchedulerConfig(Model\PrepareFormEvent $event): void
+    {
+        $form = $event->getForm();
+        $data = $event->getData();
+
+        if (
+            $form->getName() !== 'com_config.component'
+            || $this->getApplication()->getInput()->get('component') !== 'com_scheduler'
+        ) {
+            return;
+        }
+
+        if (!empty($data['webcron']['key'])) {
+            $form->removeField('generate_key_on_save', 'webcron');
+
+            $relative = 'index.php?option=com_ajax&plugin=RunSchedulerWebcron&group=system&format=json&hash=' . $data['webcron']['key'];
+            $link     = Route::link('site', $relative, false, Route::TLS_IGNORE, true);
+            $form->setValue('base_link', 'webcron', $link);
+        } else {
+            $form->removeField('base_link', 'webcron');
+            $form->removeField('reset_key', 'webcron');
+        }
+    }
+
+    /**
+     * Auto-generate a key/hash for the webcron functionality.
+     * This method acts on table save, when a hash doesn't already exist or a reset is required.
+     * @todo Move to another plugin?
+     *
+     * @param   EventInterface  $event The onExtensionBeforeSave event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     */
+    public function generateWebcronKey(EventInterface $event): void
+    {
+        /** @var Extension $table */
+        [$context, $table] = array_values($event->getArguments());
+
+        if ($context !== 'com_config.component' || $table->name !== 'com_scheduler') {
+            return;
+        }
+
+        $params = new Registry($table->params ?? '');
+
+        if (
+            empty($params->get('webcron.key'))
+            || $params->get('webcron.reset_key') === 1
+        ) {
+            $params->set('webcron.key', UserHelper::genRandomPassword(self::WEBCRON_KEY_LENGTH));
+        }
+
+        $params->remove('webcron.base_link');
+        $params->remove('webcron.reset_key');
+        $table->params = $params->toString();
+    }
+}

plugins/system/schemaorg/forms/schemaorg.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fields name="schema">
+		<fieldset
+			name="schema"
+			label="PLG_SYSTEM_SCHEMAORG_FIELD_SCHEMA_LABEL"
+		>
+			<field
+				name="schemainfo"
+				type="note"
+				class="alert alert-info d-block w-100"
+				description="PLG_SYSTEM_SCHEMAORG_FIELD_SCHEMA_DESCRIPTION"
+			/>
+			<field
+				name="schemaType"
+				type="list"
+				label="PLG_SYSTEM_SCHEMAORG_FIELD_SCHEMA_TYPE_LABEL"
+				default="None"
+				validate="options"
+				>
+				<option value="None">JNONE</option>
+			</field>
+
+		</fieldset>
+	</fields>
+</form>

plugins/system/schemaorg/schemaorg.xml

@@ -0,0 +1,77 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_schemaorg</name>
+	<author>Joomla! Project</author>
+	<creationDate>2023-07</creationDate>
+	<copyright>(C) 2023 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>5.0.0</version>
+	<description>PLG_SYSTEM_SCHEMAORG_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Schemaorg</namespace>
+	<files>
+		<folder plugin="schemaorg">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_schemaorg.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_schemaorg.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="baseType"
+					type="list"
+					label="PLG_SYSTEM_SCHEMAORG_BASETYPE_LABEL"
+					description="PLG_SYSTEM_SCHEMAORG_BASETYPE_DESCRIPTION"
+					default="organization"
+					validate="options"
+					required="true"
+					>
+					<option value="organization">PLG_SYSTEM_SCHEMAORG_BASETYPE_OPTION_ORGANIZATION</option>
+					<option value="person">PLG_SYSTEM_SCHEMAORG_BASETYPE_OPTION_PERSON</option>
+				</field>
+
+				<field
+					name="user"
+					type="user"
+					label="PLG_SYSTEM_SCHEMAORG_USER_LABEL"
+					showon="baseType:person"
+					default="0"
+				/>
+
+				<field
+					name="name"
+					type="text"
+					label="PLG_SYSTEM_SCHEMAORG_NAME_LABEL"
+					showon="baseType:organization[OR]user:0"
+				/>
+
+				<field
+					name="image"
+					type="media"
+					label="PLG_SYSTEM_SCHEMAORG_IMAGE_LABEL"
+				/>
+				<field
+					name="socialmedia"
+					type="subform"
+					label="PLG_SYSTEM_SCHEMAORG_SOCIALMEDIA_LABEL"
+					multiple="true"
+				>
+					<form>
+						<field
+							name="url"
+							type="url"
+							label="PLG_SYSTEM_SCHEMAORG_SOCIALMEDIA_URL_LABEL"
+							required="true"
+							hint="https://"
+							validate="url"
+						/>
+					</form>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/schemaorg/services/provider.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.schemaorg
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserFactoryInterface;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Schemaorg\Extension\Schemaorg;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   5.0.0
+     */
+    public function register(Container $container)
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $dispatcher = $container->get(DispatcherInterface::class);
+
+                $plugin = new Schemaorg(
+                    $dispatcher,
+                    (array) PluginHelper::getPlugin('system', 'schemaorg')
+                );
+
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase(Factory::getContainer()->get(DatabaseInterface::class));
+                $plugin->setUserFactory($container->get(UserFactoryInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/schemaorg/src/Extension/Schemaorg.php

@@ -0,0 +1,533 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.schemaorg
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Schemaorg\Extension;
+
+use Joomla\CMS\Event\Model;
+use Joomla\CMS\Event\Plugin\System\Schemaorg\BeforeCompileHeadEvent;
+use Joomla\CMS\Event\Plugin\System\Schemaorg\PrepareDataEvent;
+use Joomla\CMS\Event\Plugin\System\Schemaorg\PrepareFormEvent;
+use Joomla\CMS\Event\Plugin\System\Schemaorg\PrepareSaveEvent;
+use Joomla\CMS\Helper\ModuleHelper;
+use Joomla\CMS\HTML\HTMLHelper;
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Schemaorg\SchemaorgPrepareDateTrait;
+use Joomla\CMS\Schemaorg\SchemaorgPrepareImageTrait;
+use Joomla\CMS\Schemaorg\SchemaorgServiceInterface;
+use Joomla\CMS\Uri\Uri;
+use Joomla\CMS\User\UserFactoryAwareTrait;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Database\ParameterType;
+use Joomla\Event\SubscriberInterface;
+use Joomla\Registry\Registry;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Schemaorg System Plugin
+ *
+ * @since  5.0.0
+ */
+final class Schemaorg extends CMSPlugin implements SubscriberInterface
+{
+    use DatabaseAwareTrait;
+    use SchemaorgPrepareImageTrait;
+    use SchemaorgPrepareDateTrait;
+    use UserFactoryAwareTrait;
+
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * @return  array
+     *
+     * @since   5.0.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onBeforeCompileHead'  => 'onBeforeCompileHead',
+            'onContentPrepareData' => 'onContentPrepareData',
+            'onContentPrepareForm' => 'onContentPrepareForm',
+            'onContentAfterSave'   => 'onContentAfterSave',
+        ];
+    }
+
+    /**
+     * Runs on content preparation
+     *
+     * @param   Model\PrepareDataEvent  $event  The event
+     *
+     * @since   5.0.0
+     *
+     */
+    public function onContentPrepareData(Model\PrepareDataEvent $event)
+    {
+        $context = $event->getContext();
+        $data    = $event->getData();
+
+        $app = $this->getApplication();
+
+        if ($app->isClient('site') || !$this->isSupported($context)) {
+            return;
+        }
+
+        $data = (object) $data;
+
+        $itemId = $data->id ?? 0;
+
+        // Check if the form already has some data
+        if ($itemId > 0) {
+            $db = $this->getDatabase();
+
+            $query = $db->getQuery(true)
+                ->select('*')
+                ->from($db->quoteName('#__schemaorg'))
+                ->where($db->quoteName('itemId') . '= :itemId')
+                ->bind(':itemId', $itemId, ParameterType::INTEGER)
+                ->where($db->quoteName('context') . '= :context')
+                ->bind(':context', $context, ParameterType::STRING);
+
+            $results = $db->setQuery($query)->loadAssoc();
+
+            if (empty($results)) {
+                return;
+            }
+
+            $schemaType                 = $results['schemaType'];
+            $data->schema['schemaType'] = $schemaType;
+
+            $schema = new Registry($results['schema']);
+
+            $data->schema[$schemaType] = $schema->toArray();
+        }
+
+        $dispatcher = $this->getDispatcher();
+        $event      = new PrepareDataEvent('onSchemaPrepareData', [
+            'subject' => $data,
+            'context' => $context,
+        ]);
+
+        PluginHelper::importPlugin('schemaorg', null, true, $dispatcher);
+        $dispatcher->dispatch('onSchemaPrepareData', $event);
+    }
+
+    /**
+     * The form event.
+     *
+     * @param   Model\PrepareFormEvent  $event  The event
+     *
+     * @since   5.0.0
+     */
+    public function onContentPrepareForm(Model\PrepareFormEvent $event)
+    {
+        $form    = $event->getForm();
+        $context = $form->getName();
+        $app     = $this->getApplication();
+
+        if (!$app->isClient('administrator') || !$this->isSupported($context)) {
+            return;
+        }
+
+        // Load plugin language files.
+        $this->loadLanguage();
+
+        // Load the form fields
+        $form->loadFile(JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name . '/forms/schemaorg.xml');
+
+
+        // The user should configure the plugin first
+        if (!$this->params->get('baseType')) {
+            $form->removeField('schemaType', 'schema');
+
+            $plugin = PluginHelper::getPlugin('system', 'schemaorg');
+
+            $user = $this->getApplication()->getIdentity();
+
+            $infoText = Text::_('PLG_SYSTEM_SCHEMAORG_FIELD_SCHEMA_DESCRIPTION_NOT_CONFIGURATED');
+
+            // If edit permission are available, offer a link
+            if ($user->authorise('core.edit', 'com_plugins')) {
+                $infoText = Text::sprintf('PLG_SYSTEM_SCHEMAORG_FIELD_SCHEMA_DESCRIPTION_NOT_CONFIGURATED_ADMIN', (int) $plugin->id);
+            }
+
+            $form->setFieldAttribute('schemainfo', 'description', $infoText, 'schema');
+
+            return;
+        }
+
+        $dispatcher = $this->getDispatcher();
+        $event      = new PrepareFormEvent('onSchemaPrepareForm', [
+            'subject' => $form,
+        ]);
+
+        PluginHelper::importPlugin('schemaorg', null, true, $dispatcher);
+        $dispatcher->dispatch('onSchemaPrepareForm', $event);
+    }
+
+    /**
+     * Saves form field data in the database
+     *
+     * @param   Model\AfterSaveEvent $event
+     *
+     * @return  void
+     *
+     * @since   5.0.0
+     */
+    public function onContentAfterSave(Model\AfterSaveEvent $event)
+    {
+        $context = $event->getContext();
+        $table   = $event->getItem();
+        $isNew   = $event->getIsNew();
+        $data    = $event->getData();
+        $app     = $this->getApplication();
+        $db      = $this->getDatabase();
+
+        if (!$app->isClient('administrator') || !$this->isSupported($context)) {
+            return;
+        }
+
+        $itemId = (int) $table->id;
+
+        if (empty($data['schema']) || empty($data['schema']['schemaType']) || $data['schema']['schemaType'] === 'None') {
+            $query = $db->getQuery(true);
+
+            $query->delete($db->quoteName('#__schemaorg'))
+                ->where($db->quoteName('itemId') . '= :itemId')
+                ->bind(':itemId', $itemId, ParameterType::INTEGER)
+                ->where($db->quoteName('context') . '= :context')
+                ->bind(':context', $context, ParameterType::STRING);
+
+            $db->setQuery($query)->execute();
+
+            return;
+        }
+
+        $query = $db->getQuery(true);
+
+        $query->select('*')
+            ->from($db->quoteName('#__schemaorg'))
+            ->where($db->quoteName('itemId') . '= :itemId')
+            ->bind(':itemId', $itemId, ParameterType::INTEGER)
+            ->where($db->quoteName('context') . '= :context')
+            ->bind(':context', $context, ParameterType::STRING);
+
+        $entry = $db->setQuery($query)->loadObject();
+
+        if (empty($entry->id)) {
+            $entry = new \stdClass();
+        }
+
+        $entry->itemId     = (int) $table->getId();
+        $entry->context    = $context;
+
+        if (isset($data['schema']['schemaType'])) {
+            $entry->schemaType = $data['schema']['schemaType'];
+
+            if (isset($data['schema'][$entry->schemaType])) {
+                $entry->schema = (new Registry($data['schema'][$entry->schemaType]))->toString();
+            }
+        }
+
+        $dispatcher = $this->getDispatcher();
+        $event      = new PrepareSaveEvent('onSchemaPrepareSave', [
+            'subject' => $entry,
+            'context' => $context,
+            'item'    => $table,
+            'isNew'   => $isNew,
+            'schema'  => $data['schema'],
+        ]);
+
+        PluginHelper::importPlugin('schemaorg', null, true, $dispatcher);
+        $dispatcher->dispatch('onSchemaPrepareSave', $event);
+
+        if (!isset($entry->schemaType)) {
+            return;
+        }
+
+        if (!empty($entry->id)) {
+            $db->updateObject('#__schemaorg', $entry, 'id');
+        } else {
+            $db->insertObject('#__schemaorg', $entry, 'id');
+        }
+    }
+
+    /**
+     * This event is triggered before the framework creates the Head section of the Document
+     *
+     * @return  void
+     *
+     * @since   5.0.0
+     */
+    public function onBeforeCompileHead(): void
+    {
+        $app      = $this->getApplication();
+        $baseType = $this->params->get('baseType', 'organization');
+
+        $itemId  = (int) $app->getInput()->getInt('id');
+        $option  = $app->getInput()->get('option');
+        $view    = $app->getInput()->get('view');
+        $context = $option . '.' . $view;
+
+        // We need the plugin configured at least once to add structured data
+        if (!$app->isClient('site') || !\in_array($baseType, ['organization', 'person']) || !$this->isSupported($context)) {
+            return;
+        }
+
+        $domain = Uri::root();
+
+        $isPerson = $baseType === 'person';
+
+        $schema = new Registry();
+
+        $baseSchema = [];
+
+        $baseSchema['@context'] = 'https://schema.org';
+        $baseSchema['@graph']   = [];
+
+        // Add base tag Person/Organization
+        $baseId = $domain . '#/schema/' . ucfirst($baseType) . '/base';
+
+        $siteSchema = [];
+
+        $siteSchema['@type'] = ucfirst($baseType);
+        $siteSchema['@id']   = $baseId;
+
+        $name = $this->params->get('name', $app->get('sitename'));
+
+        if ($isPerson && $this->params->get('user') > 0) {
+            $user = $this->getUserFactory()->loadUserById($this->params->get('user'));
+
+            $name = $user ? $user->name : '';
+        }
+
+        if ($name) {
+            $siteSchema['name'] = $name;
+        }
+
+        $siteSchema['url'] = $domain;
+
+        // Image
+        $image = $this->params->get('image') ? HTMLHelper::_('cleanimageUrl', $this->params->get('image')) : false;
+
+        if ($image !== false) {
+            $siteSchema['logo'] = [
+                '@type'      => 'ImageObject',
+                '@id'        => $domain . '#/schema/ImageObject/logo',
+                'url'        => $image->url,
+                'contentUrl' => $image->url,
+                'width'      => $image->attributes['width'] ?? 0,
+                'height'     => $image->attributes['height'] ?? 0,
+            ];
+
+            $siteSchema['image'] = ['@id' => $siteSchema['logo']['@id']];
+        }
+
+        // Social media accounts
+        $socialMedia = (array) $this->params->get('socialmedia', []);
+
+        if (!empty($socialMedia)) {
+            $siteSchema['sameAs'] = [];
+        }
+
+        foreach ($socialMedia as $social) {
+            $siteSchema['sameAs'][] = $social->url;
+        }
+
+        $baseSchema['@graph'][] = $siteSchema;
+
+        // Add WebSite
+        $webSiteId = $domain . '#/schema/WebSite/base';
+
+        $webSiteSchema = [];
+
+        $webSiteSchema['@type']      = 'WebSite';
+        $webSiteSchema['@id']        = $webSiteId;
+        $webSiteSchema['url']        = $domain;
+        $webSiteSchema['name']       = $app->get('sitename');
+        $webSiteSchema['publisher']  = ['@id' => $baseId];
+
+        // We support Finder actions
+        $finder = ModuleHelper::getModule('mod_finder');
+
+        if (!empty($finder->id)) {
+            $webSiteSchema['potentialAction'] = [
+                '@type'       => 'SearchAction',
+                'target'      => Route::_('index.php?option=com_finder&view=search&q={search_term_string}', true, Route::TLS_IGNORE, true),
+                'query-input' => 'required name=search_term_string',
+            ];
+        }
+
+        $baseSchema['@graph'][] = $webSiteSchema;
+
+        // Add WebPage
+        $webPageId = $domain . '#/schema/WebPage/base';
+
+        $webPageSchema = [];
+
+        $webPageSchema['@type']       = 'WebPage';
+        $webPageSchema['@id']         = $webPageId;
+        $webPageSchema['url']         = htmlspecialchars(Uri::getInstance()->toString());
+        $webPageSchema['name']        = $app->getDocument()->getTitle();
+        $webPageSchema['description'] = $app->getDocument()->getDescription();
+        $webPageSchema['isPartOf']    = ['@id' => $webSiteId];
+        $webPageSchema['about']       = ['@id' => $baseId];
+        $webPageSchema['inLanguage']  = $app->getLanguage()->getTag();
+
+        // We support Breadcrumb linking
+        $breadcrumbs = ModuleHelper::getModule('mod_breadcrumbs');
+
+        if (!empty($breadcrumbs->id)) {
+            $webPageSchema['breadcrumb'] = ['@id' => $domain . '#/schema/BreadcrumbList/' . (int) $breadcrumbs->id];
+        }
+
+        $baseSchema['@graph'][] = $webPageSchema;
+
+        if ($itemId > 0) {
+            // Load the table data from the database
+            $db    = $this->getDatabase();
+            $query = $db->getQuery(true)
+                ->select('*')
+                ->from($db->quoteName('#__schemaorg'))
+                ->where($db->quoteName('itemId') . ' = :itemId')
+                ->bind(':itemId', $itemId, ParameterType::INTEGER)
+                ->where($db->quoteName('context') . ' = :context')
+                ->bind(':context', $context, ParameterType::STRING);
+
+            $result = $db->setQuery($query)->loadObject();
+
+            if ($result) {
+                $localSchema = new Registry($result->schema);
+
+                $localSchema->set('@id', $domain . '#/schema/' . str_replace('.', '/', $context) . '/' . (int) $result->itemId);
+                $localSchema->set('isPartOf', ['@id' => $webPageId]);
+
+                $itemSchema = $localSchema->toArray();
+
+                $baseSchema['@graph'][] = $itemSchema;
+            }
+        }
+
+        $schema->loadArray($baseSchema);
+
+        $dispatcher = $this->getDispatcher();
+        $event      = new BeforeCompileHeadEvent('onSchemaBeforeCompileHead', [
+            'subject' => $schema,
+            'context' => $context . '.' . $itemId,
+        ]);
+
+        PluginHelper::importPlugin('schemaorg', null, true, $dispatcher);
+        $dispatcher->dispatch('onSchemaBeforeCompileHead', $event);
+
+        $data = $schema->get('@graph');
+
+        foreach ($data as $key => $entry) {
+            $data[$key] = $this->cleanupSchema($entry);
+        }
+
+        $schema->set('@graph', $data);
+
+        $prettyPrint  = JDEBUG ? JSON_PRETTY_PRINT : 0;
+        $schemaString = $schema->toString('JSON', ['bitmask' => JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | $prettyPrint]);
+
+        if ($schemaString !== '{}') {
+            $wa = $this->getApplication()->getDocument()->getWebAssetManager();
+            $wa->addInlineScript($schemaString, ['name' => 'inline.schemaorg'], ['type' => 'application/ld+json']);
+        }
+    }
+
+    /**
+     * Clean the schema and remove empty fields
+     *
+     * @param   array  $schema
+     *
+     * @return  array
+     *
+     * @since  5.0.0
+     */
+    private function cleanupSchema($schema)
+    {
+        $result = [];
+
+        foreach ($schema as $key => $value) {
+            if (\is_array($value)) {
+                // Subtypes need special handling
+                if (!empty($value['@type'])) {
+                    if ($value['@type'] === 'ImageObject') {
+                        if (!empty($value['url'])) {
+                            $value['url'] = $this->prepareImage($value['url']);
+                        }
+
+                        if (empty($value['url'])) {
+                            $value = [];
+                        }
+                    } elseif ($value['@type'] === 'Date') {
+                        if (!empty($value['value'])) {
+                            $value['value'] = $this->prepareDate($value['value']);
+                        }
+
+                        if (empty($value['value'])) {
+                            $value = [];
+                        }
+                    }
+
+                    // Go into the array
+                    $value = $this->cleanupSchema($value);
+
+                    // We don't save when the array contains only the @type
+                    if (empty($value) || \count($value) <= 1) {
+                        $value = null;
+                    }
+                } elseif ($key == 'genericField') {
+                    foreach ($value as $field) {
+                        $result[$field['genericTitle']] = $field['genericValue'];
+                    }
+
+                    continue;
+                }
+            }
+
+            // No data, no play
+            if (empty($value)) {
+                continue;
+            }
+
+            $result[$key] = $value;
+        }
+
+        return $result;
+    }
+
+    /**
+     * Check if the current plugin should execute schemaorg related activities
+     *
+     * @param   string  $context
+     *
+     * @return   boolean
+     *
+     * @since   5.0.0
+     */
+    protected function isSupported($context)
+    {
+        // We need at least the extension + view for loading the table fields
+        if (!str_contains($context, '.')) {
+            return false;
+        }
+
+        $parts     = explode('.', $context, 2);
+        $component = $this->getApplication()->bootComponent($parts[0]);
+
+        return $component instanceof SchemaorgServiceInterface;
+    }
+}

plugins/system/sef/sef.xml

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_sef</name>
+	<author>Joomla! Project</author>
+	<creationDate>2007-12</creationDate>
+	<copyright>(C) 2007 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.0.0</version>
+	<description>PLG_SEF_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Sef</namespace>
+	<files>
+		<folder plugin="sef">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_sef.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_sef.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="domain"
+					type="url"
+					label="PLG_SEF_DOMAIN_LABEL"
+					description="PLG_SEF_DOMAIN_DESCRIPTION"
+					hint="https://www.example.com"
+					filter="url"
+					validate="url"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/sef/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.sef
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Sef\Extension\Sef;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Sef(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'sef')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/sef/src/Extension/Sef.php

@@ -0,0 +1,218 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.sef
+ *
+ * @copyright   (C) 2007 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Sef\Extension;
+
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Uri\Uri;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Joomla! SEF Plugin.
+ *
+ * @since  1.5
+ */
+final class Sef extends CMSPlugin
+{
+    /**
+     * Add the canonical uri to the head.
+     *
+     * @return  void
+     *
+     * @since   3.5
+     */
+    public function onAfterDispatch()
+    {
+        $doc = $this->getApplication()->getDocument();
+
+        if (!$this->getApplication()->isClient('site') || $doc->getType() !== 'html') {
+            return;
+        }
+
+        $sefDomain = $this->params->get('domain', false);
+
+        // Don't add a canonical html tag if no alternative domain has added in SEF plugin domain field.
+        if (empty($sefDomain)) {
+            return;
+        }
+
+        // Check if a canonical html tag already exists (for instance, added by a component).
+        $canonical = '';
+
+        foreach ($doc->_links as $linkUrl => $link) {
+            if (isset($link['relation']) && $link['relation'] === 'canonical') {
+                $canonical = $linkUrl;
+                break;
+            }
+        }
+
+        // If a canonical html tag already exists get the canonical and change it to use the SEF plugin domain field.
+        if (!empty($canonical)) {
+            // Remove current canonical link.
+            unset($doc->_links[$canonical]);
+
+            // Set the current canonical link but use the SEF system plugin domain field.
+            $canonical = $sefDomain . Uri::getInstance($canonical)->toString(['path', 'query', 'fragment']);
+        } else {
+            // If a canonical html doesn't exists already add a canonical html tag using the SEF plugin domain field.
+            $canonical = $sefDomain . Uri::getInstance()->toString(['path', 'query', 'fragment']);
+        }
+
+        // Add the canonical link.
+        $doc->addHeadLink(htmlspecialchars($canonical), 'canonical');
+    }
+
+    /**
+     * Convert the site URL to fit to the HTTP request.
+     *
+     * @return  void
+     */
+    public function onAfterRender()
+    {
+        if (!$this->getApplication()->isClient('site')) {
+            return;
+        }
+
+        // Replace src links.
+        $base   = Uri::base(true) . '/';
+        $buffer = $this->getApplication()->getBody();
+
+        // For feeds we need to search for the URL with domain.
+        $prefix = $this->getApplication()->getDocument()->getType() === 'feed' ? Uri::root() : '';
+
+        // Replace index.php URI by SEF URI.
+        if (strpos($buffer, 'href="' . $prefix . 'index.php?') !== false) {
+            preg_match_all('#href="' . $prefix . 'index.php\?([^"]+)"#m', $buffer, $matches);
+
+            foreach ($matches[1] as $urlQueryString) {
+                $buffer = str_replace(
+                    'href="' . $prefix . 'index.php?' . $urlQueryString . '"',
+                    'href="' . trim($prefix, '/') . Route::_('index.php?' . $urlQueryString) . '"',
+                    $buffer
+                );
+            }
+
+            $this->checkBuffer($buffer);
+        }
+
+        // Check for all unknown protocols (a protocol must contain at least one alphanumeric character followed by a ":").
+        $protocols  = '[a-zA-Z0-9\-]+:';
+        $attributes = ['href=', 'src=', 'poster='];
+
+        foreach ($attributes as $attribute) {
+            if (strpos($buffer, $attribute) !== false) {
+                $regex  = '#\s' . $attribute . '"(?!/|' . $protocols . '|\#|\')([^"]*)"#m';
+                $buffer = preg_replace($regex, ' ' . $attribute . '"' . $base . '$1"', $buffer);
+                $this->checkBuffer($buffer);
+            }
+        }
+
+        if (strpos($buffer, 'srcset=') !== false) {
+            $regex = '#\s+srcset="([^"]+)"#m';
+
+            $buffer = preg_replace_callback(
+                $regex,
+                function ($match) use ($base, $protocols) {
+                    preg_match_all('#(?:[^\s]+)\s*(?:[\d\.]+[wx])?(?:\,\s*)?#i', $match[1], $matches);
+
+                    foreach ($matches[0] as &$src) {
+                        $src = preg_replace('#^(?!/|' . $protocols . '|\#|\')(.+)#', $base . '$1', $src);
+                    }
+
+                    return ' srcset="' . implode($matches[0]) . '"';
+                },
+                $buffer
+            );
+
+            $this->checkBuffer($buffer);
+        }
+
+        // Replace all unknown protocols in javascript window open events.
+        if (strpos($buffer, 'window.open(') !== false) {
+            $regex  = '#onclick="window.open\(\'(?!/|' . $protocols . '|\#)([^/]+[^\']*?\')#m';
+            $buffer = preg_replace($regex, 'onclick="window.open(\'' . $base . '$1', $buffer);
+            $this->checkBuffer($buffer);
+        }
+
+        // Replace all unknown protocols in onmouseover and onmouseout attributes.
+        $attributes = ['onmouseover=', 'onmouseout='];
+
+        foreach ($attributes as $attribute) {
+            if (strpos($buffer, $attribute) !== false) {
+                $regex  = '#' . $attribute . '"this.src=([\']+)(?!/|' . $protocols . '|\#|\')([^"]+)"#m';
+                $buffer = preg_replace($regex, $attribute . '"this.src=$1' . $base . '$2"', $buffer);
+                $this->checkBuffer($buffer);
+            }
+        }
+
+        // Replace all unknown protocols in CSS background image.
+        if (strpos($buffer, 'style=') !== false) {
+            $regex_url  = '\s*url\s*\(([\'\"]|\&\#0?3[49];)?(?!/|\&\#0?3[49];|' . $protocols . '|\#)([^\)\'\"]+)([\'\"]|\&\#0?3[49];)?\)';
+            $regex      = '#style=\s*([\'\"])(.*):' . $regex_url . '#m';
+            $buffer     = preg_replace($regex, 'style=$1$2: url($3' . $base . '$4$5)', $buffer);
+            $this->checkBuffer($buffer);
+        }
+
+        // Replace all unknown protocols in OBJECT param tag.
+        if (strpos($buffer, '<param') !== false) {
+            // OBJECT <param name="xx", value="yy"> -- fix it only inside the <param> tag.
+            $regex  = '#(<param\s+)name\s*=\s*"(movie|src|url)"[^>]\s*value\s*=\s*"(?!/|' . $protocols . '|\#|\')([^"]*)"#m';
+            $buffer = preg_replace($regex, '$1name="$2" value="' . $base . '$3"', $buffer);
+            $this->checkBuffer($buffer);
+
+            // OBJECT <param value="xx", name="yy"> -- fix it only inside the <param> tag.
+            $regex  = '#(<param\s+[^>]*)value\s*=\s*"(?!/|' . $protocols . '|\#|\')([^"]*)"\s*name\s*=\s*"(movie|src|url)"#m';
+            $buffer = preg_replace($regex, '<param value="' . $base . '$2" name="$3"', $buffer);
+            $this->checkBuffer($buffer);
+        }
+
+        // Replace all unknown protocols in OBJECT tag.
+        if (strpos($buffer, '<object') !== false) {
+            $regex  = '#(<object\s+[^>]*)data\s*=\s*"(?!/|' . $protocols . '|\#|\')([^"]*)"#m';
+            $buffer = preg_replace($regex, '$1data="' . $base . '$2"', $buffer);
+            $this->checkBuffer($buffer);
+        }
+
+        // Use the replaced HTML body.
+        $this->getApplication()->setBody($buffer);
+    }
+
+    /**
+     * Check the buffer.
+     *
+     * @param   string  $buffer  Buffer to be checked.
+     *
+     * @return  void
+     */
+    private function checkBuffer($buffer)
+    {
+        if ($buffer === null) {
+            switch (preg_last_error()) {
+                case PREG_BACKTRACK_LIMIT_ERROR:
+                    $message = 'PHP regular expression limit reached (pcre.backtrack_limit)';
+                    break;
+                case PREG_RECURSION_LIMIT_ERROR:
+                    $message = 'PHP regular expression limit reached (pcre.recursion_limit)';
+                    break;
+                case PREG_BAD_UTF8_ERROR:
+                    $message = 'Bad UTF8 passed to PCRE function';
+                    break;
+                default:
+                    $message = 'Unknown PCRE error calling PCRE function';
+            }
+
+            throw new \RuntimeException($message);
+        }
+    }
+}

plugins/system/shortcut/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.shortcut
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Shortcut\Extension\Shortcut;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.2.0
+     */
+    public function register(Container $container)
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Shortcut(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'shortcut')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/shortcut/shortcut.xml

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_shortcut</name>
+	<author>Joomla! Project</author>
+	<creationDate>2022-06</creationDate>
+	<copyright>(C) 2022 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.2.0</version>
+	<description>PLG_SYSTEM_SHORTCUT_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Shortcut</namespace>
+	<media destination="plg_system_shortcut" folder="media">
+		<folder>js</folder>
+	</media>
+	<files>
+		<folder plugin="shortcut">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_shortcut.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_shortcut.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="timeout"
+					type="number"
+					label="PLG_SYSTEM_SHORTCUT_TIMEOUT_LABEL"
+					description="PLG_SYSTEM_SHORTCUT_TIMEOUT_DESC"
+					required="true"
+					start="1"
+					step="1"
+					default="2000"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/shortcut/src/Extension/Shortcut.php

@@ -0,0 +1,136 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.shortcut
+ *
+ * @copyright   (C) 2022 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Shortcut\Extension;
+
+use Joomla\CMS\Event\GenericEvent;
+use Joomla\CMS\Language\Text;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\Router\Route;
+use Joomla\CMS\Uri\Uri;
+use Joomla\Event\Event;
+use Joomla\Event\SubscriberInterface;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Shortcut plugin to add accessible keyboard shortcuts to the administrator templates.
+ *
+ * @since  4.2.0
+ */
+final class Shortcut extends CMSPlugin implements SubscriberInterface
+{
+    /**
+     * Returns an array of events this subscriber will listen to.
+     *
+     * The array keys are event names and the value can be:
+     *
+     *  - The method name to call (priority defaults to 0)
+     *  - An array composed of the method name to call and the priority
+     *
+     * For instance:
+     *
+     *  * array('eventName' => 'methodName')
+     *  * array('eventName' => array('methodName', $priority))
+     *
+     * @return  array
+     *
+     * @since   4.2.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onBeforeCompileHead' => 'initialize',
+            'onLoadShortcuts'     => 'addShortcuts',
+        ];
+    }
+
+    /**
+     * Add the javascript for the shortcuts
+     *
+     * @return  void
+     *
+     * @since   4.2.0
+     */
+    public function initialize()
+    {
+        if (!$this->getApplication()->isClient('administrator')) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        $context = $this->getApplication()->getInput()->get('option') . '.' . $this->getApplication()->getInput()->get('view');
+
+        $shortcuts = [];
+
+        $event = new GenericEvent(
+            'onLoadShortcuts',
+            [
+                'context'   => $context,
+                'shortcuts' => $shortcuts,
+            ]
+        );
+
+        $this->getDispatcher()->dispatch('onLoadShortcuts', $event);
+
+        $shortcuts = $event->getArgument('shortcuts');
+
+        Text::script('PLG_SYSTEM_SHORTCUT_OVERVIEW_HINT');
+        Text::script('PLG_SYSTEM_SHORTCUT_OVERVIEW_TITLE');
+        Text::script('PLG_SYSTEM_SHORTCUT_OVERVIEW_DESC');
+        Text::script('PLG_SYSTEM_SHORTCUT_THEN');
+        Text::script('JCLOSE');
+
+        $document = $this->getApplication()->getDocument();
+        $wa       = $document->getWebAssetManager();
+        $wa->useScript('bootstrap.modal');
+        $wa->registerAndUseScript('script', 'plg_system_shortcut/shortcut.min.js', ['dependencies' => ['hotkeysjs']]);
+
+        $timeout = $this->params->get('timeout', 2000);
+
+        $document->addScriptOptions('plg_system_shortcut.shortcuts', $shortcuts);
+        $document->addScriptOptions('plg_system_shortcut.timeout', $timeout);
+    }
+
+    /**
+     * Add default shortcuts to the document
+     *
+     * @param   Event  $event  The event
+     *
+     * @return  void
+     *
+     * @since   4.2.0
+     */
+    public function addShortcuts(Event $event)
+    {
+        $shortcuts = $event->getArgument('shortcuts', []);
+
+        $shortcuts = array_merge(
+            $shortcuts,
+            [
+                'applyKey'   => (object) ['selector' => 'joomla-toolbar-button .button-apply', 'shortcut' => 'A', 'title' => $this->getApplication()->getLanguage()->_('JAPPLY')],
+                'saveKey'    => (object) ['selector' => 'joomla-toolbar-button .button-save', 'shortcut' => 'S', 'title' => $this->getApplication()->getLanguage()->_('JTOOLBAR_SAVE')],
+                'cancelKey'  => (object) ['selector' => 'joomla-toolbar-button .button-cancel', 'shortcut' => 'Q', 'title' => $this->getApplication()->getLanguage()->_('JCANCEL')],
+                'newKey'     => (object) ['selector' => 'joomla-toolbar-button .button-new', 'shortcut' => 'N', 'title' => $this->getApplication()->getLanguage()->_('JTOOLBAR_NEW')],
+                'searchKey'  => (object) ['selector' => 'input[placeholder=' . $this->getApplication()->getLanguage()->_('JSEARCH_FILTER') . ']', 'shortcut' => 'F', 'title' => $this->getApplication()->getLanguage()->_('JSEARCH_FILTER')],
+                'optionKey'  => (object) ['selector' => 'joomla-toolbar-button .button-options', 'shortcut' => 'O', 'title' => $this->getApplication()->getLanguage()->_('JOPTIONS')],
+                'helpKey'    => (object) ['selector' => 'joomla-toolbar-button .button-help', 'shortcut' => 'H', 'title' => $this->getApplication()->getLanguage()->_('JHELP')],
+                'toggleMenu' => (object) ['selector' => '#menu-collapse', 'shortcut' => 'M', 'title' => $this->getApplication()->getLanguage()->_('JTOGGLE_SIDEBAR_MENU')],
+                'dashboard'  => (object) ['selector' => (string) new Uri(Route::_('index.php?')), 'shortcut' => 'D', 'title' => $this->getApplication()->getLanguage()->_('JHOMEDASHBOARD')],
+            ]
+        );
+
+        $event->setArgument('shortcuts', $shortcuts);
+    }
+}

plugins/system/skipto/services/provider.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.skipto
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Skipto\Extension\Skipto;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Skipto(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'skipto')
+                );
+                $plugin->setApplication(Factory::getApplication());
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/skipto/skipto.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_skipto</name>
+	<author>Joomla! Project</author>
+	<creationDate>2020-02</creationDate>
+	<copyright>(C) 2019 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.0.0</version>
+	<description>PLG_SYSTEM_SKIPTO_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Skipto</namespace>
+	<files>
+		<folder plugin="skipto">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_skipto.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_skipto.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic">
+				<field
+					name="section"
+					type="list"
+					label="PLG_SYSTEM_SKIPTO_SECTION"
+					default="administrator"
+					validate="options"
+					>
+					<option value="site">PLG_SYSTEM_SKIPTO_SECTION_SITE</option>
+					<option value="administrator">PLG_SYSTEM_SKIPTO_SECTION_ADMIN</option>
+					<option value="both">PLG_SYSTEM_SKIPTO_SECTION_BOTH</option>
+				</field>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/skipto/src/Extension/Skipto.php

@@ -0,0 +1,102 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.skipto
+ *
+ * @copyright   (C) 2020 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Skipto\Extension;
+
+use Joomla\CMS\Plugin\CMSPlugin;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Skipto plugin to add accessible keyboard navigation to the site and administrator templates.
+ *
+ * @since  4.0.0
+ */
+final class Skipto extends CMSPlugin
+{
+    /**
+     * Add the skipto navigation menu.
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onAfterDispatch()
+    {
+        $section = $this->params->get('section', 'administrator');
+
+        if ($section !== 'both' && $this->getApplication()->isClient($section) !== true) {
+            return;
+        }
+
+        // Get the document object.
+        $document = $this->getApplication()->getDocument();
+
+        if ($document->getType() !== 'html') {
+            return;
+        }
+
+        // Are we in a modal?
+        if ($this->getApplication()->getInput()->get('tmpl', '', 'cmd') === 'component') {
+            return;
+        }
+
+        // Load language file.
+        $this->loadLanguage();
+
+        // Add plugin settings and strings for translations in JavaScript.
+        $document->addScriptOptions(
+            'skipto-settings',
+            [
+                'settings' => [
+                    'skipTo' => [
+                        // Feature switches
+                        'enableActions'               => false,
+                        'enableHeadingLevelShortcuts' => false,
+
+                        // Customization of button and menu
+                        'accesskey'     => '9',
+                        'displayOption' => 'popup',
+
+                        // Button labels and messages
+                        'buttonLabel'            => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_TITLE'),
+                        'buttonTooltipAccesskey' => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_ACCESS_KEY'),
+
+                        // Menu labels and messages
+                        'landmarkGroupLabel'  => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK'),
+                        'headingGroupLabel'   => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_HEADING'),
+                        'mofnGroupLabel'      => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_HEADING_MOFN'),
+                        'headingLevelLabel'   => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_HEADING_LEVEL'),
+                        'mainLabel'           => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_MAIN'),
+                        'searchLabel'         => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_SEARCH'),
+                        'navLabel'            => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_NAV'),
+                        'regionLabel'         => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_REGION'),
+                        'asideLabel'          => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_ASIDE'),
+                        'footerLabel'         => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_FOOTER'),
+                        'headerLabel'         => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_HEADER'),
+                        'formLabel'           => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_FORM'),
+                        'msgNoLandmarksFound' => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_LANDMARK_NONE'),
+                        'msgNoHeadingsFound'  => $this->getApplication()->getLanguage()->_('PLG_SYSTEM_SKIPTO_HEADING_NONE'),
+
+                        // Selectors for landmark and headings sections
+                        'headings'  => 'h1, h2, h3',
+                        'landmarks' => 'main, nav, search, aside, header, footer, form',
+                    ],
+                ],
+            ]
+        );
+
+        /** @var \Joomla\CMS\WebAsset\WebAssetManager $wa */
+        $wa = $document->getWebAssetManager();
+        $wa->useScript('skipto');
+    }
+}

plugins/system/stats/layouts/field/data.php

@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\Language\Text;
+
+/** @var Joomla\CMS\WebAsset\WebAssetManager $wa */
+$wa = Factory::getApplication()->getDocument()->getWebAssetManager();
+$wa->registerAndUseScript('plg_system_stats.stats', 'plg_system_stats/stats.js', [], ['defer' => true], ['core']);
+
+extract($displayData);
+
+/**
+ * Layout variables
+ * -----------------
+ * @var   string   $autocomplete    Autocomplete attribute for the field.
+ * @var   boolean  $autofocus       Is autofocus enabled?
+ * @var   string   $class           Classes for the input.
+ * @var   string   $description     Description of the field.
+ * @var   boolean  $disabled        Is this field disabled?
+ * @var   string   $group           Group the field belongs to. <fields> section in form XML.
+ * @var   boolean  $hidden          Is this field hidden in the form?
+ * @var   string   $hint            Placeholder for the field.
+ * @var   string   $id              DOM id of the field.
+ * @var   string   $label           Label of the field.
+ * @var   string   $labelclass      Classes to apply to the label.
+ * @var   boolean  $multiple        Does this field support multiple values?
+ * @var   string   $name            Name of the input field.
+ * @var   string   $onchange        Onchange attribute for the field.
+ * @var   string   $onclick         Onclick attribute for the field.
+ * @var   string   $pattern         Pattern (Reg Ex) of value of the form field.
+ * @var   boolean  $readonly        Is this field read only?
+ * @var   boolean  $repeat          Allows extensions to duplicate elements.
+ * @var   boolean  $required        Is this field required?
+ * @var   integer  $size            Size attribute of the input.
+ * @var   boolean  $spellcheck      Spellcheck state for the form field.
+ * @var   string   $validate        Validation rules to apply.
+ * @var   string   $value           Value attribute of the field.
+ * @var   array    $options         Options available for this field.
+ * @var   array    $statsData       Statistics that will be sent to the stats server
+ */
+?>
+<?php if (count($statsData)) : ?>
+    <a href="#" id="js-pstats-data-details-toggler"><?php echo Text::_('PLG_SYSTEM_STATS_MSG_WHAT_DATA_WILL_BE_SENT'); ?></a>
+    <?php echo $field->render('stats', compact('statsData')); ?>
+<?php endif; ?>

plugins/system/stats/layouts/field/uniqueid.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\Language\Text;
+
+extract($displayData);
+
+/**
+ * Layout variables
+ * -----------------
+ * @var   string   $autocomplete    Autocomplete attribute for the field.
+ * @var   boolean  $autofocus       Is autofocus enabled?
+ * @var   string   $class           Classes for the input.
+ * @var   string   $description     Description of the field.
+ * @var   boolean  $disabled        Is this field disabled?
+ * @var   string   $group           Group the field belongs to. <fields> section in form XML.
+ * @var   boolean  $hidden          Is this field hidden in the form?
+ * @var   string   $hint            Placeholder for the field.
+ * @var   string   $id              DOM id of the field.
+ * @var   string   $label           Label of the field.
+ * @var   string   $labelclass      Classes to apply to the label.
+ * @var   boolean  $multiple        Does this field support multiple values?
+ * @var   string   $name            Name of the input field.
+ * @var   string   $onchange        Onchange attribute for the field.
+ * @var   string   $onclick         Onclick attribute for the field.
+ * @var   string   $pattern         Pattern (Reg Ex) of value of the form field.
+ * @var   boolean  $readonly        Is this field read only?
+ * @var   boolean  $repeat          Allows extensions to duplicate elements.
+ * @var   boolean  $required        Is this field required?
+ * @var   integer  $size            Size attribute of the input.
+ * @var   boolean  $spellcheck      Spellcheck state for the form field.
+ * @var   string   $validate        Validation rules to apply.
+ * @var   string   $value           Value attribute of the field.
+ * @var   array    $options         Options available for this field.
+ */
+?>
+<input type="hidden" name="<?php echo $name; ?>" id="<?php echo $id; ?>" value="<?php echo htmlspecialchars($value, ENT_QUOTES, 'UTF-8'); ?>">
+<button class="btn btn-secondary" type="button" id="js-pstats-reset-uid">
+    <span class="icon-sync"></span> <?php echo Text::_('PLG_SYSTEM_STATS_RESET_UNIQUE_ID'); ?>
+</button>

plugins/system/stats/layouts/message.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2015 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\Language\Text;
+use Joomla\Registry\Registry;
+
+extract($displayData);
+
+/**
+ * Layout variables
+ * -----------------
+ * @var  PlgSystemStats  $plugin        Plugin rendering this layout
+ * @var  Registry        $pluginParams  Plugin parameters
+ * @var  array           $statsData     Array containing the data that will be sent to the stats server
+ */
+?>
+
+<joomla-alert type="info" dismiss class="js-pstats-alert hidden" role="alertdialog" close-text="<?php echo Text::_('JCLOSE'); ?>" aria-labelledby="alert-stats-heading">
+    <div class="alert-heading" id="alert-stats-heading"><?php echo Text::_('PLG_SYSTEM_STATS_LABEL_MESSAGE_TITLE'); ?></div>
+    <div>
+        <div class="alert-message">
+            <p>
+                <?php echo Text::_('PLG_SYSTEM_STATS_MSG_JOOMLA_WANTS_TO_SEND_DATA'); ?>
+            </p>
+            <p>
+                <a href="#" class="js-pstats-btn-details alert-link"><?php echo Text::_('PLG_SYSTEM_STATS_MSG_WHAT_DATA_WILL_BE_SENT'); ?></a>
+            </p>
+            <?php
+                echo $plugin->render('stats', compact('statsData'));
+            ?>
+            <p class="fw-bold"><?php echo Text::_('PLG_SYSTEM_STATS_MSG_ALLOW_SENDING_DATA'); ?></p>
+            <p class="actions">
+                <button type="button" class="btn btn-primary js-pstats-btn-allow-never"><?php echo Text::_('PLG_SYSTEM_STATS_BTN_NEVER_SEND'); ?></button>
+                <button type="button" class="btn btn-primary js-pstats-btn-allow-always"><?php echo Text::_('PLG_SYSTEM_STATS_BTN_SEND_ALWAYS'); ?></button>
+            </p>
+        </div>
+    </div>
+</joomla-alert>

plugins/system/stats/layouts/stats.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\Language\Text;
+
+extract($displayData);
+
+/**
+ * Layout variables
+ * -----------------
+ * @var   array  $statsData  Array containing the data that will be sent to the stats server
+ */
+
+$versionFields = ['php_version', 'db_version', 'cms_version'];
+?>
+<table class="table mb-3 d-none" id="js-pstats-data-details">
+    <caption class="visually-hidden">
+        <?php echo Text::_('PLG_SYSTEM_STATS_STATISTICS'); ?>
+    </caption>
+    <thead>
+        <tr>
+            <th scope="col" class="w-15">
+                <?php echo Text::_('PLG_SYSTEM_STATS_SETTING'); ?>
+            </th>
+            <th scope="col">
+                <?php echo Text::_('PLG_SYSTEM_STATS_VALUE'); ?>
+            </th>
+        </tr>
+    </thead>
+    <tbody>
+    <?php foreach ($statsData as $key => $value) : ?>
+        <tr>
+            <th scope="row"><?php echo Text::_('PLG_SYSTEM_STATS_LABEL_' . strtoupper($key)); ?></th>
+            <td><?php echo in_array($key, $versionFields) ? (preg_match('/\d+(?:\.\d+)+/', $value, $matches) ? $matches[0] : $value) : $value; ?></td>
+        </tr>
+    <?php endforeach; ?>
+    </tbody>
+</table>

plugins/system/stats/services/provider.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\Stats\Extension\Stats;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new Stats(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'stats')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/stats/src/Extension/Stats.php

@@ -0,0 +1,620 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2015 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Stats\Extension;
+
+use Joomla\CMS\Cache\Cache;
+use Joomla\CMS\Http\HttpFactory;
+use Joomla\CMS\Layout\FileLayout;
+use Joomla\CMS\Log\Log;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\User\UserHelper;
+use Joomla\Database\DatabaseAwareTrait;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+// Uncomment the following line to enable debug mode for testing purposes. Note: statistics will be sent on every page load
+// define('PLG_SYSTEM_STATS_DEBUG', 1);
+
+/**
+ * Statistics system plugin. This sends anonymous data back to the Joomla! Project about the
+ * PHP, SQL, Joomla and OS versions
+ *
+ * @since  3.5
+ */
+final class Stats extends CMSPlugin
+{
+    use DatabaseAwareTrait;
+
+    /**
+     * Indicates sending statistics is always allowed.
+     *
+     * @var    integer
+     *
+     * @since  3.5
+     */
+    public const MODE_ALLOW_ALWAYS = 1;
+
+    /**
+     * Indicates sending statistics is never allowed.
+     *
+     * @var    integer
+     *
+     * @since  3.5
+     */
+    public const MODE_ALLOW_NEVER = 3;
+
+    /**
+     * URL to send the statistics.
+     *
+     * @var    string
+     *
+     * @since  3.5
+     */
+    protected $serverUrl = 'https://developer.joomla.org/stats/submit';
+
+    /**
+     * Unique identifier for this site
+     *
+     * @var    string
+     *
+     * @since  3.5
+     */
+    protected $uniqueId;
+
+    /**
+     * Listener for the `onAfterInitialise` event
+     *
+     * @return  void
+     *
+     * @since   3.5
+     */
+    public function onAfterInitialise()
+    {
+        if (!$this->getApplication()->isClient('administrator') || !$this->isAllowedUser()) {
+            return;
+        }
+
+        if ($this->isCaptiveMFA()) {
+            return;
+        }
+
+        if (!$this->isDebugEnabled() && !$this->isUpdateRequired()) {
+            return;
+        }
+
+        if ($this->getApplication()->getInput()->getVar('tmpl') === 'component') {
+            return;
+        }
+
+        // Load plugin language files only when needed (ex: they are not needed in site client).
+        $this->loadLanguage();
+    }
+
+    /**
+     * Listener for the `onAfterDispatch` event
+     *
+     * @return  void
+     *
+     * @since   4.0.0
+     */
+    public function onAfterDispatch()
+    {
+        if (!$this->getApplication()->isClient('administrator') || !$this->isAllowedUser()) {
+            return;
+        }
+
+        if ($this->isCaptiveMFA()) {
+            return;
+        }
+
+        if (!$this->isDebugEnabled() && !$this->isUpdateRequired()) {
+            return;
+        }
+
+        if ($this->getApplication()->getInput()->getVar('tmpl') === 'component') {
+            return;
+        }
+
+        if ($this->getApplication()->getDocument()->getType() !== 'html') {
+            return;
+        }
+
+        $this->getApplication()->getDocument()->getWebAssetManager()
+            ->registerAndUseScript('plg_system_stats.message', 'plg_system_stats/stats-message.js', [], ['defer' => true], ['core']);
+    }
+
+    /**
+     * User selected to always send data
+     *
+     * @return  void
+     *
+     * @since   3.5
+     *
+     * @throws  \Exception         If user is not allowed.
+     * @throws  \RuntimeException  If there is an error saving the params or sending the data.
+     */
+    public function onAjaxSendAlways()
+    {
+        if (!$this->isAllowedUser() || !$this->isAjaxRequest()) {
+            throw new \Exception($this->getApplication()->getLanguage()->_('JGLOBAL_AUTH_ACCESS_DENIED'), 403);
+        }
+
+        $this->params->set('mode', static::MODE_ALLOW_ALWAYS);
+
+        if (!$this->saveParams()) {
+            throw new \RuntimeException('Unable to save plugin settings', 500);
+        }
+
+        echo json_encode(['sent' => (int) $this->sendStats()]);
+    }
+
+    /**
+     * User selected to never send data.
+     *
+     * @return  void
+     *
+     * @since   3.5
+     *
+     * @throws  \Exception         If user is not allowed.
+     * @throws  \RuntimeException  If there is an error saving the params.
+     */
+    public function onAjaxSendNever()
+    {
+        if (!$this->isAllowedUser() || !$this->isAjaxRequest()) {
+            throw new \Exception($this->getApplication()->getLanguage()->_('JGLOBAL_AUTH_ACCESS_DENIED'), 403);
+        }
+
+        $this->params->set('mode', static::MODE_ALLOW_NEVER);
+
+        if (!$this->saveParams()) {
+            throw new \RuntimeException('Unable to save plugin settings', 500);
+        }
+
+        if (!$this->disablePlugin()) {
+            throw new \RuntimeException('Unable to disable the statistics plugin', 500);
+        }
+
+        echo json_encode(['sent' => 0]);
+    }
+
+    /**
+     * Send the stats to the server.
+     * On first load | on demand mode it will show a message asking users to select mode.
+     *
+     * @return  void
+     *
+     * @since   3.5
+     *
+     * @throws  \Exception         If user is not allowed.
+     * @throws  \RuntimeException  If there is an error saving the params, disabling the plugin or sending the data.
+     */
+    public function onAjaxSendStats()
+    {
+        if (!$this->isAllowedUser() || !$this->isAjaxRequest()) {
+            throw new \Exception($this->getApplication()->getLanguage()->_('JGLOBAL_AUTH_ACCESS_DENIED'), 403);
+        }
+
+        // User has not selected the mode. Show message.
+        if ((int) $this->params->get('mode') !== static::MODE_ALLOW_ALWAYS) {
+            $data = [
+                'sent' => 0,
+                'html' => $this->getRenderer('message')->render($this->getLayoutData()),
+            ];
+
+            echo json_encode($data);
+
+            return;
+        }
+
+        if (!$this->saveParams()) {
+            throw new \RuntimeException('Unable to save plugin settings', 500);
+        }
+
+        echo json_encode(['sent' => (int) $this->sendStats()]);
+    }
+
+    /**
+     * Get the data through events
+     *
+     * @param   string  $context  Context where this will be called from
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    public function onGetStatsData($context)
+    {
+        return $this->getStatsData();
+    }
+
+    /**
+     * Debug a layout of this plugin
+     *
+     * @param   string  $layoutId  Layout identifier
+     * @param   array   $data      Optional data for the layout
+     *
+     * @return  string
+     *
+     * @since   3.5
+     */
+    public function debug($layoutId, $data = [])
+    {
+        $data = array_merge($this->getLayoutData(), $data);
+
+        return $this->getRenderer($layoutId)->debug($data);
+    }
+
+    /**
+     * Get the data for the layout
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    private function getLayoutData()
+    {
+        return [
+            'plugin'       => $this,
+            'pluginParams' => $this->params,
+            'statsData'    => $this->getStatsData(),
+        ];
+    }
+
+    /**
+     * Get the layout paths
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    private function getLayoutPaths()
+    {
+        $template = $this->getApplication()->getTemplate();
+
+        return [
+            JPATH_ADMINISTRATOR . '/templates/' . $template . '/html/layouts/plugins/' . $this->_type . '/' . $this->_name,
+            JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name . '/layouts',
+        ];
+    }
+
+    /**
+     * Get the plugin renderer
+     *
+     * @param   string  $layoutId  Layout identifier
+     *
+     * @return  \Joomla\CMS\Layout\LayoutInterface
+     *
+     * @since   3.5
+     */
+    private function getRenderer($layoutId = 'default')
+    {
+        $renderer = new FileLayout($layoutId);
+
+        $renderer->setIncludePaths($this->getLayoutPaths());
+
+        return $renderer;
+    }
+
+    /**
+     * Get the data that will be sent to the stats server.
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    private function getStatsData()
+    {
+        $data = [
+            'unique_id'   => $this->getUniqueId(),
+            'php_version' => PHP_VERSION,
+            'db_type'     => $this->getDatabase()->name,
+            'db_version'  => $this->getDatabase()->getVersion(),
+            'cms_version' => JVERSION,
+            'server_os'   => php_uname('s') . ' ' . php_uname('r'),
+        ];
+
+        // Check if we have a MariaDB version string and extract the proper version from it
+        if (preg_match('/^(?:5\.5\.5-)?(mariadb-)?(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)/i', $data['db_version'], $versionParts)) {
+            $data['db_version'] = $versionParts['major'] . '.' . $versionParts['minor'] . '.' . $versionParts['patch'];
+        }
+
+        return $data;
+    }
+
+    /**
+     * Get the unique id. Generates one if none is set.
+     *
+     * @return  integer
+     *
+     * @since   3.5
+     */
+    private function getUniqueId()
+    {
+        if (null === $this->uniqueId) {
+            $this->uniqueId = $this->params->get('unique_id', hash('sha1', UserHelper::genRandomPassword(28) . time()));
+        }
+
+        return $this->uniqueId;
+    }
+
+    /**
+     * Check if current user is allowed to send the data
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     */
+    private function isAllowedUser()
+    {
+        return $this->getApplication()->getIdentity() && $this->getApplication()->getIdentity()->authorise('core.admin');
+    }
+
+    /**
+     * Check if the debug is enabled
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     */
+    private function isDebugEnabled()
+    {
+        return \defined('PLG_SYSTEM_STATS_DEBUG');
+    }
+
+    /**
+     * Check if last_run + interval > now
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     */
+    private function isUpdateRequired()
+    {
+        $last     = (int) $this->params->get('lastrun', 0);
+        $interval = (int) $this->params->get('interval', 12);
+        $mode     = (int) $this->params->get('mode', 0);
+
+        if ($mode === static::MODE_ALLOW_NEVER) {
+            return false;
+        }
+
+        // Never updated or debug enabled
+        if (!$last || $this->isDebugEnabled()) {
+            return true;
+        }
+
+        return abs(time() - $last) > $interval * 3600;
+    }
+
+    /**
+     * Check valid AJAX request
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     */
+    private function isAjaxRequest()
+    {
+        return strtolower($this->getApplication()->getInput()->server->get('HTTP_X_REQUESTED_WITH', '')) === 'xmlhttprequest';
+    }
+
+    /**
+     * Render a layout of this plugin
+     *
+     * @param   string  $layoutId  Layout identifier
+     * @param   array   $data      Optional data for the layout
+     *
+     * @return  string
+     *
+     * @since   3.5
+     */
+    public function render($layoutId, $data = [])
+    {
+        $data = array_merge($this->getLayoutData(), $data);
+
+        return $this->getRenderer($layoutId)->render($data);
+    }
+
+    /**
+     * Save the plugin parameters
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     */
+    private function saveParams()
+    {
+        // Update params
+        $this->params->set('lastrun', time());
+        $this->params->set('unique_id', $this->getUniqueId());
+        $interval = (int) $this->params->get('interval', 12);
+        $this->params->set('interval', $interval ?: 12);
+
+        $paramsJson = $this->params->toString('JSON');
+        $db         = $this->getDatabase();
+
+        $query = $db->getQuery(true)
+            ->update($db->quoteName('#__extensions'))
+            ->set($db->quoteName('params') . ' = :params')
+            ->where($db->quoteName('type') . ' = ' . $db->quote('plugin'))
+            ->where($db->quoteName('folder') . ' = ' . $db->quote('system'))
+            ->where($db->quoteName('element') . ' = ' . $db->quote('stats'))
+            ->bind(':params', $paramsJson);
+
+        try {
+            // Lock the tables to prevent multiple plugin executions causing a race condition
+            $db->lockTable('#__extensions');
+        } catch (\Exception $e) {
+            // If we can't lock the tables it's too risky to continue execution
+            return false;
+        }
+
+        try {
+            // Update the plugin parameters
+            $result = $db->setQuery($query)->execute();
+
+            $this->clearCacheGroups(['com_plugins']);
+        } catch (\Exception $exc) {
+            // If we failed to execute
+            $db->unlockTables();
+            $result = false;
+        }
+
+        try {
+            // Unlock the tables after writing
+            $db->unlockTables();
+        } catch (\Exception $e) {
+            // If we can't lock the tables assume we have somehow failed
+            $result = false;
+        }
+
+        return $result;
+    }
+
+    /**
+     * Send the stats to the stats server
+     *
+     * @return  boolean
+     *
+     * @since   3.5
+     *
+     * @throws  \RuntimeException  If there is an error sending the data and debug mode enabled.
+     */
+    private function sendStats()
+    {
+        $error = false;
+
+        try {
+            // Don't let the request take longer than 2 seconds to avoid page timeout issues
+            $response = HttpFactory::getHttp()->post($this->serverUrl, $this->getStatsData(), [], 2);
+
+            if (!$response) {
+                $error = 'Could not send site statistics to remote server: No response';
+            } elseif ($response->code !== 200) {
+                $data = json_decode($response->body);
+
+                $error = 'Could not send site statistics to remote server: ' . $data->message;
+            }
+        } catch (\UnexpectedValueException $e) {
+            // There was an error sending stats. Should we do anything?
+            $error = 'Could not send site statistics to remote server: ' . $e->getMessage();
+        } catch (\RuntimeException $e) {
+            // There was an error connecting to the server or in the post request
+            $error = 'Could not connect to statistics server: ' . $e->getMessage();
+        } catch (\Exception $e) {
+            // An unexpected error in processing; don't let this failure kill the site
+            $error = 'Unexpected error connecting to statistics server: ' . $e->getMessage();
+        }
+
+        if ($error !== false) {
+            // Log any errors if logging enabled.
+            Log::add($error, Log::WARNING, 'jerror');
+
+            // If Stats debug mode enabled, or Global Debug mode enabled, show error to the user.
+            if ($this->isDebugEnabled() || $this->getApplication()->get('debug')) {
+                throw new \RuntimeException($error, 500);
+            }
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Clears cache groups. We use it to clear the plugins cache after we update the last run timestamp.
+     *
+     * @param   array  $clearGroups  The cache groups to clean
+     *
+     * @return  void
+     *
+     * @since   3.5
+     */
+    private function clearCacheGroups(array $clearGroups)
+    {
+        foreach ($clearGroups as $group) {
+            try {
+                $options = [
+                    'defaultgroup' => $group,
+                    'cachebase'    => $this->getApplication()->get('cache_path', JPATH_CACHE),
+                ];
+
+                $cache = Cache::getInstance('callback', $options);
+                $cache->clean();
+            } catch (\Exception $e) {
+                // Ignore it
+            }
+        }
+    }
+
+    /**
+     * Disable this plugin, if user selects once or never, to stop Joomla loading the plugin on every page load and
+     * therefore regaining a tiny bit of performance
+     *
+     * @since   4.0.0
+     *
+     * @return  boolean
+     */
+    private function disablePlugin()
+    {
+        $db = $this->getDatabase();
+
+        $query = $db->getQuery(true)
+            ->update($db->quoteName('#__extensions'))
+            ->set($db->quoteName('enabled') . ' = 0')
+            ->where($db->quoteName('type') . ' = ' . $db->quote('plugin'))
+            ->where($db->quoteName('folder') . ' = ' . $db->quote('system'))
+            ->where($db->quoteName('element') . ' = ' . $db->quote('stats'));
+
+        try {
+            // Lock the tables to prevent multiple plugin executions causing a race condition
+            $db->lockTable('#__extensions');
+        } catch (\Exception $e) {
+            // If we can't lock the tables it's too risky to continue execution
+            return false;
+        }
+
+        try {
+            // Update the plugin parameters
+            $result = $db->setQuery($query)->execute();
+
+            $this->clearCacheGroups(['com_plugins']);
+        } catch (\Exception $exc) {
+            // If we failed to execute
+            $db->unlockTables();
+            $result = false;
+        }
+
+        try {
+            // Unlock the tables after writing
+            $db->unlockTables();
+        } catch (\Exception $e) {
+            // If we can't lock the tables assume we have somehow failed
+            $result = false;
+        }
+
+        return $result;
+    }
+
+    /**
+     * Are we in a Multi-factor Authentication page?
+     *
+     * @return  bool
+     * @since   4.2.1
+     */
+    private function isCaptiveMFA(): bool
+    {
+        return method_exists($this->getApplication(), 'isMultiFactorAuthenticationPage')
+            && $this->getApplication()->isMultiFactorAuthenticationPage(true);
+    }
+}

plugins/system/stats/src/Field/AbstractStatsField.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Stats\Field;
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\Form\FormField;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Base field for the Stats Plugin.
+ *
+ * @since  3.5
+ */
+abstract class AbstractStatsField extends FormField
+{
+    /**
+     * Get the layouts paths
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    protected function getLayoutPaths()
+    {
+        $template = Factory::getApplication()->getTemplate();
+
+        return [
+            JPATH_ADMINISTRATOR . '/templates/' . $template . '/html/layouts/plugins/system/stats',
+            JPATH_PLUGINS . '/system/stats/layouts',
+            JPATH_SITE . '/layouts',
+        ];
+    }
+}

plugins/system/stats/src/Field/DataField.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Stats\Field;
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Unique ID Field class for the Stats Plugin.
+ *
+ * @since  3.5
+ */
+class DataField extends AbstractStatsField
+{
+    /**
+     * The form field type.
+     *
+     * @var    string
+     * @since  3.5
+     */
+    protected $type = 'Data';
+
+    /**
+     * Name of the layout being used to render the field
+     *
+     * @var    string
+     * @since  3.5
+     */
+    protected $layout = 'field.data';
+
+    /**
+     * Method to get the data to be passed to the layout for rendering.
+     *
+     * @return  array
+     *
+     * @since   3.5
+     */
+    protected function getLayoutData()
+    {
+        $data       = parent::getLayoutData();
+
+        PluginHelper::importPlugin('system', 'stats');
+
+        $result = Factory::getApplication()->triggerEvent('onGetStatsData', ['stats.field.data']);
+
+        $data['statsData'] = $result ? reset($result) : [];
+
+        return $data;
+    }
+}

plugins/system/stats/src/Field/UniqueidField.php

@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.stats
+ *
+ * @copyright   (C) 2016 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\Stats\Field;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * Unique ID Field class for the Stats Plugin.
+ *
+ * @since  3.5
+ */
+class UniqueidField extends AbstractStatsField
+{
+    /**
+     * The form field type.
+     *
+     * @var    string
+     * @since  3.5
+     */
+    protected $type = 'Uniqueid';
+
+    /**
+     * Name of the layout being used to render the field
+     *
+     * @var    string
+     * @since  3.5
+     */
+    protected $layout = 'field.uniqueid';
+}

plugins/system/stats/stats.xml

@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_stats</name>
+	<author>Joomla! Project</author>
+	<creationDate>2013-11</creationDate>
+	<copyright>(C) 2013 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>3.5.0</version>
+	<description>PLG_SYSTEM_STATS_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\Stats</namespace>
+	<files>
+		<folder>layouts</folder>
+		<folder plugin="stats">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_stats.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_stats.sys.ini</language>
+	</languages>
+	<config>
+		<fields name="params">
+			<fieldset name="basic" addfieldprefix="Joomla\Plugin\System\Stats\Field">
+				<field
+					name="data"
+					type="data"
+					label=""
+				/>
+
+				<field
+					name="unique_id"
+					type="uniqueid"
+					label="PLG_SYSTEM_STATS_UNIQUE_ID_LABEL"
+				/>
+
+				<field
+					name="interval"
+					type="number"
+					label="PLG_SYSTEM_STATS_INTERVAL_LABEL"
+					filter="integer"
+					default="12"
+				/>
+
+				<field
+					name="mode"
+					type="list"
+					label="PLG_SYSTEM_STATS_MODE_LABEL"
+					default="1"
+					validate="options"
+					>
+					<option value="2">PLG_SYSTEM_STATS_MODE_OPTION_ON_DEMAND</option>
+					<option value="1">PLG_SYSTEM_STATS_MODE_OPTION_ALWAYS_SEND</option>
+					<option value="3">PLG_SYSTEM_STATS_MODE_OPTION_NEVER_SEND</option>
+				</field>
+
+				<field
+					name="lastrun"
+					type="hidden"
+					default="0"
+				/>
+			</fieldset>
+		</fields>
+	</config>
+</extension>

plugins/system/tasknotification/forms/task_notification.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form>
+	<fields name="params">
+		<fields name="notifications">
+			<fieldset name="notifications">
+				<field
+					name="success_mail"
+					type="radio"
+					label="PLG_SYSTEM_TASK_NOTIFICATION_LABEL_SUCCESS_MAIL_TOGGLE"
+					layout="joomla.form.field.radio.switcher"
+					default="0"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="failure_mail"
+					type="radio"
+					label="PLG_SYSTEM_TASK_NOTIFICATION_LABEL_FAILURE_MAIL_TOGGLE"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="fatal_failure_mail"
+					type="radio"
+					label="PLG_SYSTEM_TASK_NOTIFICATION_LABEL_FATAL_FAILURE_MAIL_TOGGLE"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+				<field
+					name="orphan_mail"
+					type="radio"
+					label="PLG_SYSTEM_TASK_NOTIFICATION_LABEL_ORPHANED_TASK_MAIL_TOGGLE"
+					layout="joomla.form.field.radio.switcher"
+					default="1"
+					>
+					<option value="0">JDISABLED</option>
+					<option value="1">JENABLED</option>
+				</field>
+			</fieldset>
+		</fields>
+	</fields>
+</form>

plugins/system/tasknotification/services/provider.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * @package     Joomla.Plugin
+ * @subpackage  System.tasknotification
+ *
+ * @copyright   (C) 2023 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+\defined('_JEXEC') or die;
+
+use Joomla\CMS\Extension\PluginInterface;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Plugin\PluginHelper;
+use Joomla\CMS\User\UserFactoryInterface;
+use Joomla\Database\DatabaseInterface;
+use Joomla\DI\Container;
+use Joomla\DI\ServiceProviderInterface;
+use Joomla\Event\DispatcherInterface;
+use Joomla\Plugin\System\TaskNotification\Extension\TaskNotification;
+
+return new class () implements ServiceProviderInterface {
+    /**
+     * Registers the service provider with a DI container.
+     *
+     * @param   Container  $container  The DI container.
+     *
+     * @return  void
+     *
+     * @since   4.4.0
+     */
+    public function register(Container $container): void
+    {
+        $container->set(
+            PluginInterface::class,
+            function (Container $container) {
+                $plugin     = new TaskNotification(
+                    $container->get(DispatcherInterface::class),
+                    (array) PluginHelper::getPlugin('system', 'tasknotification')
+                );
+                $plugin->setApplication(Factory::getApplication());
+                $plugin->setDatabase($container->get(DatabaseInterface::class));
+                $plugin->setUserFactory($container->get(UserFactoryInterface::class));
+
+                return $plugin;
+            }
+        );
+    }
+};

plugins/system/tasknotification/src/Extension/TaskNotification.php

@@ -0,0 +1,317 @@
+<?php
+
+/**
+ * @package     Joomla.Plugins
+ * @subpackage  System.tasknotification
+ *
+ * @copyright   (C) 2021 Open Source Matters, Inc. <https://www.joomla.org>
+ * @license     GNU General Public License version 2 or later; see LICENSE.txt
+ */
+
+namespace Joomla\Plugin\System\TaskNotification\Extension;
+
+use Joomla\CMS\Event\Model;
+use Joomla\CMS\Factory;
+use Joomla\CMS\Log\Log;
+use Joomla\CMS\Mail\MailTemplate;
+use Joomla\CMS\Plugin\CMSPlugin;
+use Joomla\CMS\User\UserFactoryAwareTrait;
+use Joomla\Component\Scheduler\Administrator\Task\Status;
+use Joomla\Component\Scheduler\Administrator\Task\Task;
+use Joomla\Database\DatabaseAwareTrait;
+use Joomla\Event\Event;
+use Joomla\Event\SubscriberInterface;
+use Joomla\Filesystem\Path;
+use PHPMailer\PHPMailer\Exception as MailerException;
+
+// phpcs:disable PSR1.Files.SideEffects
+\defined('_JEXEC') or die;
+// phpcs:enable PSR1.Files.SideEffects
+
+/**
+ * This plugin implements email notification functionality for Tasks configured through the Scheduler component.
+ * Notification configuration is supported on a per-task basis, which can be set-up through the Task item form, made
+ * possible by injecting the notification fields into the item form with a `onContentPrepareForm` listener.<br/>
+ *
+ * Notifications can be set-up on: task success, failure, fatal failure (task running too long or crashing the request),
+ * or on _orphaned_ task routines (missing parent plugin - either uninstalled, disabled or no longer offering a routine
+ * with the same ID).
+ *
+ * @since 4.1.0
+ */
+final class TaskNotification extends CMSPlugin implements SubscriberInterface
+{
+    use DatabaseAwareTrait;
+    use UserFactoryAwareTrait;
+
+    /**
+     * The task notification form. This form is merged into the task item form by {@see
+     * injectTaskNotificationFieldset()}.
+     *
+     * @var string
+     * @since 4.1.0
+     */
+    private const TASK_NOTIFICATION_FORM = 'task_notification';
+
+    /**
+     * @inheritDoc
+     *
+     * @return array
+     *
+     * @since 4.1.0
+     */
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            'onContentPrepareForm'  => 'injectTaskNotificationFieldset',
+            'onTaskExecuteSuccess'  => 'notifySuccess',
+            'onTaskExecuteFailure'  => 'notifyFailure',
+            'onTaskRoutineNotFound' => 'notifyOrphan',
+            'onTaskRecoverFailure'  => 'notifyFatalRecovery',
+        ];
+    }
+
+    /**
+     * Inject fields to support configuration of post-execution notifications into the task item form.
+     *
+     * @param   Model\PrepareFormEvent  $event  The onContentPrepareForm event.
+     *
+     * @return boolean True if successful.
+     *
+     * @since 4.1.0
+     */
+    public function injectTaskNotificationFieldset(Model\PrepareFormEvent $event): bool
+    {
+        $form = $event->getForm();
+
+        if ($form->getName() !== 'com_scheduler.task') {
+            return true;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        $formFile = JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name . '/forms/' . self::TASK_NOTIFICATION_FORM . '.xml';
+
+        try {
+            $formFile = Path::check($formFile);
+        } catch (\Exception $e) {
+            // Log?
+            return false;
+        }
+
+        $formFile = Path::clean($formFile);
+
+        if (!is_file($formFile)) {
+            return false;
+        }
+
+        return $form->loadFile($formFile);
+    }
+
+    /**
+     * Send out email notifications on Task execution failure if task configuration allows it.
+     *
+     * @param   Event  $event  The onTaskExecuteFailure event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \Exception
+     */
+    public function notifyFailure(Event $event): void
+    {
+        /** @var Task $task */
+        $task = $event->getArgument('subject');
+
+        if (!(int) $task->get('params.notifications.failure_mail', 1)) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        // @todo safety checks, multiple files [?]
+        $outFile = $event->getArgument('subject')->snapshot['output_file'] ?? '';
+        $data    = $this->getDataFromTask($event->getArgument('subject'));
+        $this->sendMail('plg_system_tasknotification.failure_mail', $data, $outFile);
+    }
+
+    /**
+     * Send out email notifications on orphaned task if task configuration allows.<br/>
+     * A task is `orphaned` if the task's parent plugin has been removed/disabled, or no longer offers a task
+     * with the same routine ID.
+     *
+     * @param   Event  $event  The onTaskRoutineNotFound event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \Exception
+     */
+    public function notifyOrphan(Event $event): void
+    {
+        /** @var Task $task */
+        $task = $event->getArgument('subject');
+
+        if (!(int) $task->get('params.notifications.orphan_mail', 1)) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        $data = $this->getDataFromTask($event->getArgument('subject'));
+        $this->sendMail('plg_system_tasknotification.orphan_mail', $data);
+    }
+
+    /**
+     * Send out email notifications on Task execution success if task configuration allows.
+     *
+     * @param   Event  $event  The onTaskExecuteSuccess event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \Exception
+     */
+    public function notifySuccess(Event $event): void
+    {
+        /** @var Task $task */
+        $task = $event->getArgument('subject');
+
+        if (!(int) $task->get('params.notifications.success_mail', 0)) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        // @todo safety checks, multiple files [?]
+        $outFile = $event->getArgument('subject')->snapshot['output_file'] ?? '';
+        $data    = $this->getDataFromTask($event->getArgument('subject'));
+        $this->sendMail('plg_system_tasknotification.success_mail', $data, $outFile);
+    }
+
+    /**
+     * Send out email notifications on fatal recovery of task execution if task configuration allows.<br/>
+     * Fatal recovery indicated that the task either crashed the parent process or its execution lasted longer
+     * than the global task timeout (this is configurable through the Scheduler component configuration).
+     * In the latter case, the global task timeout should be adjusted so that this false positive can be avoided.
+     * This stands as a limitation of the Scheduler's current task execution implementation, which doesn't involve
+     * keeping track of the parent PHP process which could enable keeping track of the task's status.
+     *
+     * @param   Event  $event  The onTaskRecoverFailure event.
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \Exception
+     */
+    public function notifyFatalRecovery(Event $event): void
+    {
+        /** @var Task $task */
+        $task = $event->getArgument('subject');
+
+        if (!(int) $task->get('params.notifications.fatal_failure_mail', 1)) {
+            return;
+        }
+
+        // Load translations
+        $this->loadLanguage();
+
+        $data = $this->getDataFromTask($event->getArgument('subject'));
+        $this->sendMail('plg_system_tasknotification.fatal_recovery_mail', $data);
+    }
+
+    /**
+     * @param   Task  $task  A task object
+     *
+     * @return array  An array of data to bind to a mail template.
+     *
+     * @since 4.1.0
+     */
+    private function getDataFromTask(Task $task): array
+    {
+        $lockOrExecTime = Factory::getDate($task->get('locked') ?? $task->get('last_execution'))->format($this->getApplication()->getLanguage()->_('DATE_FORMAT_LC2'));
+
+        return [
+            'TASK_ID'        => $task->get('id'),
+            'TASK_TITLE'     => $task->get('title'),
+            'EXIT_CODE'      => $task->getContent()['status'] ?? Status::NO_EXIT,
+            'EXEC_DATE_TIME' => $lockOrExecTime,
+            'TASK_OUTPUT'    => $task->getContent()['output_body'] ?? '',
+        ];
+    }
+
+    /**
+     * @param   string  $template    The mail template.
+     * @param   array   $data        The data to bind to the mail template.
+     * @param   string  $attachment  The attachment to send with the mail (@todo multiple)
+     *
+     * @return void
+     *
+     * @since 4.1.0
+     * @throws \Exception
+     */
+    private function sendMail(string $template, array $data, string $attachment = ''): void
+    {
+        $app = $this->getApplication();
+        $db  = $this->getDatabase();
+
+        // Get all users who are not blocked and have opted in for system mails.
+        $query = $db->getQuery(true);
+
+        $query->select($db->quoteName(['name', 'email', 'sendEmail', 'id']))
+            ->from($db->quoteName('#__users'))
+            ->where($db->quoteName('sendEmail') . ' = 1')
+            ->where($db->quoteName('block') . ' = 0');
+
+        $db->setQuery($query);
+
+        try {
+            $users = $db->loadObjectList();
+        } catch (\RuntimeException $e) {
+            return;
+        }
+
+        if ($users === null) {
+            Log::add($this->getApplication()->getLanguage()->_('PLG_SYSTEM_TASK_NOTIFICATION_USER_FETCH_FAIL'), Log::ERROR);
+
+            return;
+        }
+
+        $mailSent = false;
+
+        // Mail all matching users who also have the `core.manage` privilege for com_scheduler.
+        foreach ($users as $user) {
+            $user = $this->getUserFactory()->loadUserById($user->id);
+
+            if ($user->authorise('core.manage', 'com_scheduler')) {
+                try {
+                    $mailer = new MailTemplate($template, $app->getLanguage()->getTag());
+                    $mailer->addTemplateData($data);
+                    $mailer->addRecipient($user->email);
+
+                    if (
+                        !empty($attachment)
+                        && is_file($attachment)
+                    ) {
+                        // @todo we allow multiple files [?]
+                        $attachName = pathinfo($attachment, PATHINFO_BASENAME);
+                        $mailer->addAttachment($attachName, $attachment);
+                    }
+
+                    $mailer->send();
+                    $mailSent = true;
+                } catch (MailerException $exception) {
+                    Log::add($this->getApplication()->getLanguage()->_('PLG_SYSTEM_TASK_NOTIFICATION_NOTIFY_SEND_EMAIL_FAIL'), Log::ERROR);
+                }
+            }
+        }
+
+        if (!$mailSent) {
+            Log::add($this->getApplication()->getLanguage()->_('PLG_SYSTEM_TASK_NOTIFICATION_NO_MAIL_SENT'), Log::WARNING);
+        }
+    }
+}

plugins/system/tasknotification/tasknotification.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extension type="plugin" group="system" method="upgrade">
+	<name>plg_system_task_notification</name>
+	<author>Joomla! Project</author>
+	<creationDate>2021-09</creationDate>
+	<copyright>(C) 2021 Open Source Matters, Inc.</copyright>
+	<license>GNU General Public License version 2 or later; see LICENSE.txt</license>
+	<authorEmail>admin@joomla.org</authorEmail>
+	<authorUrl>www.joomla.org</authorUrl>
+	<version>4.1</version>
+	<description>PLG_SYSTEM_TASK_NOTIFICATION_XML_DESCRIPTION</description>
+	<namespace path="src">Joomla\Plugin\System\TaskNotification</namespace>
+	<files>
+		<folder>forms</folder>
+		<folder plugin="tasknotification">services</folder>
+		<folder>src</folder>
+	</files>
+	<languages>
+		<language tag="en-GB">language/en-GB/plg_system_tasknotification.ini</language>
+		<language tag="en-GB">language/en-GB/plg_system_tasknotification.sys.ini</language>
+	</languages>
+</extension>