diff --git a/Neos.Flow/Classes/Core/Bootstrap.php b/Neos.Flow/Classes/Core/Bootstrap.php
index 3b1f3a8122..0910f8937c 100644
--- a/Neos.Flow/Classes/Core/Bootstrap.php
+++ b/Neos.Flow/Classes/Core/Bootstrap.php
@@ -540,11 +540,11 @@ protected function defineConstants()
             define('FLOW_PATH_TEMPORARY', $temporaryDirectoryPath);
         }
 
-        // Not using this flag and loading classes via our class loader is deprecated
-        // and we will remove class loading from our loader in the next major of Flow (5.0).
-        $onlyUseComposerAutoLoaderForPackageClasses = false;
-        if (in_array(self::getEnvironmentConfigurationSetting('FLOW_ONLY_COMPOSER_LOADER'), [true, 'true', 1, '1'])) {
-            $onlyUseComposerAutoLoaderForPackageClasses = true;
+        // Setting this flag to false will enable the custom Class Loader on top of the default autoloading provided by composer
+        // @deprecated since Version 4.3. Packages should use the default composer autoloading mechanism
+        $onlyUseComposerAutoLoaderForPackageClasses = true;
+        if (in_array(self::getEnvironmentConfigurationSetting('FLOW_ONLY_COMPOSER_LOADER'), [false, 'false', 0, '0'])) {
+            $onlyUseComposerAutoLoaderForPackageClasses = false;
         }
 
         define('FLOW_ONLY_COMPOSER_LOADER', $onlyUseComposerAutoLoaderForPackageClasses);
diff --git a/Neos.Flow/Documentation/TheDefinitiveGuide/PartII/Configuration.rst b/Neos.Flow/Documentation/TheDefinitiveGuide/PartII/Configuration.rst
index f1e2a35837..b14fcbee83 100644
--- a/Neos.Flow/Documentation/TheDefinitiveGuide/PartII/Configuration.rst
+++ b/Neos.Flow/Documentation/TheDefinitiveGuide/PartII/Configuration.rst
@@ -195,7 +195,8 @@ Some specific flow behaviour can also be configured with a couple of environment
 | FLOW_LOCKHOLDINGPAGE      | Use to specify the html page shown when the site is locked |
 |                           | This is relative to the Packages directory                 |
 +---------------------------+------------------------------------------------------------+
-| FLOW_ONLY_COMPOSER_LOADER | Set to true (1) to only use composer autoloader            |
+| FLOW_ONLY_COMPOSER_LOADER | Set to false (0) to use the custom ClassLoader on top of   | 
+|                           | the regular mechanism provided by composer (deprecated)    |
 +---------------------------+------------------------------------------------------------+