Fatal error: Declaration of In2code\Powermail\Controller\FormController::forwardToReferringRequest() must be compatible with TYPO3\CMS\Extbase\Mvc\Controller\ActionController::forwardToReferringRequest(): ?Psr\Http\Message\ResponseInterface in /var/www/typo3v11.bauakademie-sachsen.de/typo3conf/ext/powermail/Classes/Controller/FormController.php on line 466