Fatal error: Uncaught Error: Interface "TYPO3\CMS\Backend\Template\Components\Buttons\DropDown\DropDownItemInterface" not found in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-backend/Classes/Template/Components/Buttons/DropDown/DropDownHeader.php:33 Stack trace: #0 {main} thrown in /var/www/html/dev.hallescherfc.de/vendor/typo3/cms-backend/Classes/Template/Components/Buttons/DropDown/DropDownHeader.php on line 33