WIP: Implement even more stuff

src/Menu/AdminMenuBuilder.php

@@ -143,7 +143,9 @@ class AdminMenuBuilder extends AbstractMenuBuilder
 
         $menu->addChild('zurück zur Übersicht', [
             'route' => 'app_admin_teamer_index',
-            'icon' => 'back',
+            'extras' => [
+                'icon' => 'back',
+            ],
         ]);
 
         return $menu;