diff --git a/core/modules/system/lib/Drupal/system/Tests/Menu/LocalActionTest.php b/core/modules/system/lib/Drupal/system/Tests/Menu/LocalActionTest.php
index 81fe57d..014d58f 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Menu/LocalActionTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Menu/LocalActionTest.php
@@ -40,6 +40,7 @@ public function testLocalAction() {
       'menu-test-local-action/dynamic-title' => 'My dynamic-title action',
       'menu-test-local-action/hook_menu' => 'My hook_menu action',
       'menu-test-local-action/routing' => 'My routing action',
+      'menu-test-local-action/routing' => 'My YAML discovery action',
     ));
   }
 
diff --git a/core/modules/system/tests/modules/menu_test/menu_test.local_actions.yml b/core/modules/system/tests/modules/menu_test/menu_test.local_actions.yml
index e69de29..04e9b0a 100644
--- a/core/modules/system/tests/modules/menu_test/menu_test.local_actions.yml
+++ b/core/modules/system/tests/modules/menu_test/menu_test.local_actions.yml
@@ -0,0 +1,5 @@
+menu_test_local_action4:
+ route_name: menu_test_local_action3
+ title: 'My YAML discovery action'
+ appears_on:
+   - menu_test_local_action1