Issue #3337216: DI problems

src/Plugin/Field/FieldWidget/PrivateMessageThreadMemberWidget.php

@@ -139,7 +139,7 @@ class PrivateMessageThreadMemberWidget extends EntityReferenceAutocompleteWidget
       $container->get('request_stack'),
       $container->get('entity_type.manager'),
       $container->get('config.factory'),
-      $container->get('keyvalue'),
+      $container->get('keyvalue')
     );
   }