Fatal error: Uncaught Error: Interface "Symfony\Component\Mailer\MailerInterface" not found in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-core/Classes/Mail/MailerInterface.php:27 Stack trace: #0 {main} thrown in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-core/Classes/Mail/MailerInterface.php on line 27