diff --git a/libraries/src/Application/CMSApplication.php b/libraries/src/Application/CMSApplication.php
index 3d874b8658a7..c27b4c07ae4f 100644
--- a/libraries/src/Application/CMSApplication.php
+++ b/libraries/src/Application/CMSApplication.php
@@ -14,7 +14,6 @@
 use Joomla\CMS\Authentication\Authentication;
 use Joomla\CMS\Component\ComponentHelper;
 use Joomla\CMS\Event\AbstractEvent;
-use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Event\ErrorEvent;
 use Joomla\CMS\Exception\ExceptionHandler;
 use Joomla\CMS\Extension\ExtensionManagerTrait;
@@ -227,17 +226,6 @@ public function execute()
 		{
 			$this->createExtensionNamespaceMap();
 
-			PluginHelper::importPlugin('system');
-
-			// Trigger the onBeforeExecute event
-			$this->getDispatcher()->dispatch(
-				'onBeforeExecute',
-				new BeforeExecuteEvent('onBeforeExecute', ['subject' => $this, 'container' => $this->getContainer()])
-			);
-
-			// Mark beforeExecute in the profiler.
-			JDEBUG ? $this->profiler->mark('beforeExecute event dispatched') : null;
-
 			// Perform application routines.
 			$this->doExecute();
 
diff --git a/libraries/src/Application/CliApplication.php b/libraries/src/Application/CliApplication.php
index 1a1bde534793..ea338779cc0e 100644
--- a/libraries/src/Application/CliApplication.php
+++ b/libraries/src/Application/CliApplication.php
@@ -14,7 +14,6 @@
 use Joomla\CMS\Application\CLI\CliInput;
 use Joomla\CMS\Application\CLI\CliOutput;
 use Joomla\CMS\Application\CLI\Output\Stdout;
-use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Extension\ExtensionManagerTrait;
 use Joomla\CMS\Factory;
 use Joomla\DI\Container;
@@ -149,10 +148,7 @@ public static function getInstance($name = null)
 	public function execute()
 	{
 		// Trigger the onBeforeExecute event
-		$this->getDispatcher()->dispatch(
-			'onBeforeExecute',
-			new BeforeExecuteEvent('onBeforeExecute', ['subject' => $this, 'container' => $this->getContainer()])
-		);
+		$this->triggerEevent('onBeforeExecute');
 
 		// Perform application routines.
 		$this->doExecute();
diff --git a/libraries/src/Application/DaemonApplication.php b/libraries/src/Application/DaemonApplication.php
index 5498a1e58e4b..6677084a9423 100644
--- a/libraries/src/Application/DaemonApplication.php
+++ b/libraries/src/Application/DaemonApplication.php
@@ -10,7 +10,6 @@
 
 \defined('JPATH_PLATFORM') or die;
 
-use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Filesystem\Folder;
 use Joomla\CMS\Input\Cli;
 use Joomla\CMS\Log\Log;
@@ -365,10 +364,7 @@ public function loadConfiguration($data)
 	public function execute()
 	{
 		// Trigger the onBeforeExecute event
-		$this->getDispatcher()->dispatch(
-			'onBeforeExecute',
-			new BeforeExecuteEvent('onBeforeExecute', ['subject' => $this, 'container' => $this->getContainer()])
-		);
+		$this->triggerEvent('onBeforeExecute');
 
 		// Enable basic garbage collection.
 		gc_enable();
diff --git a/libraries/src/Application/SiteApplication.php b/libraries/src/Application/SiteApplication.php
index 7592291b98e9..e787a8b95e93 100644
--- a/libraries/src/Application/SiteApplication.php
+++ b/libraries/src/Application/SiteApplication.php
@@ -587,6 +587,13 @@ protected function initialiseApp($options = array())
 			$user->groups = array($guestUsergroup);
 		}
 
+		if ($plugin = PluginHelper::getPlugin('system', 'languagefilter'))
+		{
+			$pluginParams = new Registry($plugin->params);
+			$this->setLanguageFilter(true);
+			$this->setDetectBrowser($pluginParams->get('detect_browser', 1) == 1);
+		}
+
 		if (empty($options['language']))
 		{
 			// Detect the specified language
diff --git a/libraries/src/Application/WebApplication.php b/libraries/src/Application/WebApplication.php
index d63a0a2f3eec..71bac5d60a90 100644
--- a/libraries/src/Application/WebApplication.php
+++ b/libraries/src/Application/WebApplication.php
@@ -13,7 +13,6 @@
 use Joomla\Application\AbstractWebApplication;
 use Joomla\Application\Web\WebClient;
 use Joomla\CMS\Document\Document;
-use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Input\Input;
 use Joomla\CMS\Language\Language;
@@ -132,11 +131,8 @@ public static function getInstance($name = null)
 	 */
 	public function execute()
 	{
-		// Trigger the onBeforeExecute event
-		$this->getDispatcher()->dispatch(
-			'onBeforeExecute',
-			new BeforeExecuteEvent('onBeforeExecute', ['subject' => $this, 'container' => $this->getContainer()])
-		);
+		// Trigger the onBeforeExecute event.
+		$this->triggerEvent('onBeforeExecute');
 
 		// Perform application routines.
 		$this->doExecute();
diff --git a/libraries/src/Event/BeforeExecuteEvent.php b/libraries/src/Event/BeforeExecuteEvent.php
deleted file mode 100644
index 3b3ed9ab92b4..000000000000
--- a/libraries/src/Event/BeforeExecuteEvent.php
+++ /dev/null
@@ -1,46 +0,0 @@
-<?php
-/**
- * Joomla! Content Management System
- *
- * @copyright  Copyright (C) 2005 - 2019 Open Source Matters, Inc. All rights reserved.
- * @license    GNU General Public License version 2 or later; see LICENSE
- */
-
-namespace Joomla\CMS\Event;
-
-use Joomla\Application\AbstractApplication;
-use Joomla\DI\Container;
-
-\defined('JPATH_PLATFORM') or die;
-
-/**
- * Event class for representing the application's `onBeforeExecute` event
- *
- * @since  4.0.0
- */
-class BeforeExecuteEvent extends AbstractImmutableEvent
-{
-	/**
-	 * Get the event's application object
-	 *
-	 * @return  AbstractApplication
-	 *
-	 * @since  4.0.0
-	 */
-	public function getApplication(): AbstractApplication
-	{
-		return $this->getArgument('subject');
-	}
-
-	/**
-	 * Get the event's container object
-	 *
-	 * @return  Container
-	 *
-	 * @since  4.0.0
-	 */
-	public function getContainer(): Container
-	{
-		return $this->arguments['container'];
-	}
-}
diff --git a/plugins/system/languagefilter/languagefilter.php b/plugins/system/languagefilter/languagefilter.php
index 6338c00b845f..d920128bbd62 100644
--- a/plugins/system/languagefilter/languagefilter.php
+++ b/plugins/system/languagefilter/languagefilter.php
@@ -14,7 +14,6 @@
 use Joomla\CMS\Application\CMSApplicationInterface;
 use Joomla\CMS\Association\AssociationServiceInterface;
 use Joomla\CMS\Component\ComponentHelper;
-use Joomla\CMS\Event\BeforeExecuteEvent;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Filesystem\Folder;
 use Joomla\CMS\Language\Associations;
@@ -191,30 +190,6 @@ public function onAfterRoute()
 		}
 	}
 
-	/**
-	 * Listener for the onBeforeExecute event
-	 *
-	 * @param   BeforeExecuteEvent  $event  The Event object
-	 *
-	 * @return  void
-	 *
-	 * @since   4.0
-	 */
-	public function onBeforeExecute(BeforeExecuteEvent $event)
-	{
-		/** @var \Joomla\CMS\Application\SiteApplication $app */
-		$app = $event->getApplication();
-
-		if (!$app->isClient('site'))
-		{
-			return;
-		}
-
-		// If a language was specified it has priority, otherwise use user or default language settings
-		$app->setLanguageFilter(true);
-		$app->setDetectBrowser($this->params->get('detect_browser', '1') == '1');
-	}
-
 	/**
 	 * Add build preprocess rule to router.
 	 *