diff --git a/src/Extension/ExtensionServiceProvider.php b/src/Extension/ExtensionServiceProvider.php
index 2e484bfbc..4a80efb25 100644
--- a/src/Extension/ExtensionServiceProvider.php
+++ b/src/Extension/ExtensionServiceProvider.php
@@ -24,11 +24,10 @@ class ExtensionServiceProvider extends AbstractServiceProvider
         $this->app->bind('flarum.extensions', ExtensionManager::class);
 
         $this->app->booting(function (Container $app) {
-            /** @var callable[] $extenders */
             $extenders = $app->make('flarum.extensions')->getActiveExtenders();
 
             foreach ($extenders as $extender) {
-                $app->call($extender);
+                $extender($app);
             }
         });
     }