Fatal error: Uncaught Error: Interface 'Contao\CoreBundle\Config\Dumper\DumperInterface' not found in /home/eberhardschwarze/public_html/vendor/contao/core-bundle/src/Config/Dumper/CombinedFileDumper.php:22 Stack trace: #0 {main} thrown in /home/eberhardschwarze/public_html/vendor/contao/core-bundle/src/Config/Dumper/CombinedFileDumper.php on line 22