chore:

Author: SamMousa

src/Codeception/Module/Yii2.php

@@ -848,7 +848,7 @@ public function _backupSession(): array
         return [
             'clientContext' => $this->getClient()->getContext(),
             'headers' => $this->headers,
-            'cookie' => $_COOKIE,
+            'cookie' => $_COOKIE ?? [],
             'session' => $_SESSION ?? [],
         ];
     }