diff --git a/core/modules/system/src/ModuleDependencyMessageTrait.php b/core/lib/Drupal/Core/Extension/ModuleDependencyMessageTrait.php
similarity index 96%
rename from core/modules/system/src/ModuleDependencyMessageTrait.php
rename to core/lib/Drupal/Core/Extension/ModuleDependencyMessageTrait.php
index febfbfa43fd2fb6f6d63e320f7eda4c0e06bd4f1..2440e31317f6fe1c2e60f0c9a2837082886e5c7b 100644
--- a/core/modules/system/src/ModuleDependencyMessageTrait.php
+++ b/core/lib/Drupal/Core/Extension/ModuleDependencyMessageTrait.php
@@ -1,8 +1,6 @@
 <?php
 
-namespace Drupal\system;
-
-use Drupal\Core\Extension\Dependency;
+namespace Drupal\Core\Extension;
 
 /**
  * Messages for missing or incompatible dependencies on modules.
diff --git a/core/lib/Drupal/Core/Extension/ThemeInstaller.php b/core/lib/Drupal/Core/Extension/ThemeInstaller.php
index 860d79fe8d4e2baa22dd7684300aca98e01ee0b8..d3776272432941b3d36f6a3f53b8dc973f8034a7 100644
--- a/core/lib/Drupal/Core/Extension/ThemeInstaller.php
+++ b/core/lib/Drupal/Core/Extension/ThemeInstaller.php
@@ -12,7 +12,6 @@
 use Drupal\Core\Routing\RouteBuilderInterface;
 use Drupal\Core\State\StateInterface;
 use Drupal\Core\StringTranslation\StringTranslationTrait;
-use Drupal\system\ModuleDependencyMessageTrait;
 use Psr\Log\LoggerInterface;
 
 /**
diff --git a/core/modules/system/src/Controller/SystemController.php b/core/modules/system/src/Controller/SystemController.php
index 801c12c3aaaf0deef0f1c7b915c13d2e6894e59c..f1f765d71c02803d5c4ee64435f6e0462c7a2cef 100644
--- a/core/modules/system/src/Controller/SystemController.php
+++ b/core/modules/system/src/Controller/SystemController.php
@@ -4,6 +4,7 @@
 
 use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Extension\ModuleDependencyMessageTrait;
 use Drupal\Core\Extension\ModuleExtensionList;
 use Drupal\Core\Extension\ThemeHandlerInterface;
 use Drupal\Core\Form\FormBuilderInterface;
@@ -11,7 +12,6 @@
 use Drupal\Core\Menu\MenuTreeParameters;
 use Drupal\Core\Theme\ThemeAccessCheck;
 use Drupal\Core\Url;
-use Drupal\system\ModuleDependencyMessageTrait;
 use Drupal\system\SystemManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
diff --git a/core/modules/system/src/Form/ModulesListForm.php b/core/modules/system/src/Form/ModulesListForm.php
index 66e0fbc806aea499a68dc52086c1421a17d79e57..726345eef11b611f68043401a04753869b8d6bc8 100644
--- a/core/modules/system/src/Form/ModulesListForm.php
+++ b/core/modules/system/src/Form/ModulesListForm.php
@@ -7,6 +7,7 @@
 use Drupal\Core\Access\AccessManagerInterface;
 use Drupal\Core\Extension\Extension;
 use Drupal\Core\Extension\InfoParserException;
+use Drupal\Core\Extension\ModuleDependencyMessageTrait;
 use Drupal\Core\Extension\ModuleExtensionList;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Extension\ModuleInstallerInterface;
@@ -17,7 +18,6 @@
 use Drupal\Core\Session\AccountInterface;
 use Drupal\user\PermissionHandlerInterface;
 use Drupal\Core\Url;
-use Drupal\system\ModuleDependencyMessageTrait;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**