/**
  * Only allow construction if we have a backend session
  */
 public function __construct()
 {
     if (!$this->isAuthorizedBackendSession()) {
         throw new \TYPO3\CMS\Core\Error\Exception('A back-end form protection may only be instantiated if there' . ' is an active back-end session.', 1285067843);
     }
     $this->backendUser = $GLOBALS['BE_USER'];
     parent::__construct();
 }