Fatal error: Uncaught Error: Class "TYPO3\CMS\Core\Authentication\AbstractUserAuthentication" not found in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-core/Classes/Authentication/BackendUserAuthentication.php:65 Stack trace: #0 {main} thrown in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-core/Classes/Authentication/BackendUserAuthentication.php on line 65