diff --git a/framework/web/Controller.php b/framework/web/Controller.php
index aca323eaa4..f3f538005e 100644
--- a/framework/web/Controller.php
+++ b/framework/web/Controller.php
@@ -200,6 +200,7 @@ class Controller extends \yii\base\Controller
      */
     public function redirect($url, $statusCode = 302)
     {
+        // calling Url::to() here because Response::redirect() modifies route before calling Url::to()
         return Yii::$app->getResponse()->redirect(Url::to($url), $statusCode);
     }