diff -u b/core/modules/block/src/Controller/BlockLibraryController.php b/core/modules/block/src/Controller/BlockLibraryController.php
--- b/core/modules/block/src/Controller/BlockLibraryController.php
+++ b/core/modules/block/src/Controller/BlockLibraryController.php
@@ -104,8 +104,8 @@
     $region = $request->query->get('region');
     $weight = $request->query->get('weight');
 
-    // Adds to the "Add custom block" action url route parameters, to provide
-    // correct region setting after creation.
+    // Adds route parameters for  "Add custom block" action uri
+    // Provides correct region setting on block creation.
     $add_action_url = $build['local_actions']['block_content_add_action']['#link']['url'] ?? NULL;
     if ($add_action_url instanceof Url) {
       $add_action_url->setRouteParameter('region', $region);
diff -u b/core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php b/core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php
--- b/core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php
+++ b/core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php
@@ -5,6 +5,7 @@
 use Drupal\Core\Menu\LocalActionDefault;
 use Drupal\Core\Routing\RouteMatchInterface;
 use Drupal\Core\Url;
+use Symfony\Component\HttpFoundation\RequestStack;
 
 /**
  * Modifies the 'Add custom block' local action.
@@ -13,4 +14,27 @@
 
   /**
+   * Request stack.
+   *
+   * @var \Symfony\Component\HttpFoundation\RequestStack
+   */
+  protected $requestmatch;
+
+  /**
+   * Constructor function.
+   */
+  public function __construct(RequestStack $request) {
+    $this->requestMatch = $request;
+  }
+
+  /**
+   * Creates container.
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('request_stack')
+    );
+  }
+
+  /**
    * {@inheritdoc}
    */
@@ -22,7 +46,7 @@
     }
 
     // If the current request has a region query parameter.
-    if ($region = \Drupal::request()->query->get('region')) {
+    if ($region = $this->requestMatch->query->get('region')) {
       $options['query']['region'] = $region;
     }