diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index e54cf89..9e9fe1e 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -1017,7 +1017,7 @@ protected function compileContainer() {
       $path = DRUPAL_ROOT . '/core/lib/Drupal/' . $parent_directory;
       $parent_namespace = 'Drupal\\' . $parent_directory;
       foreach (new \DirectoryIterator($path) as $component) {
-        if (!$component->isDot() && $component->isDir() && is_dir($component->getPathname() . '/Plugin')) {
+        if (!$component->isDot() && $component->isDir()) {
           $namespaces[$parent_namespace . '\\' . $component->getFilename()] = $path . '/' . $component->getFilename();
         }
       }