Fatal error: Uncaught Error: Class 'Contao\CoreBundle\Controller\AbstractFragmentController' not found in /home/benjamincb/demos/acdg-site/vendor/contao/core-bundle/src/Controller/ContentElement/AbstractContentElementController.php:21 Stack trace: #0 {main} thrown in /home/benjamincb/demos/acdg-site/vendor/contao/core-bundle/src/Controller/ContentElement/AbstractContentElementController.php on line 21