Fatal error: Uncaught Error: Class 'Symfony\Component\EventDispatcher\Event' not found in /home/likach/contao44.lika.ch/vendor/contao/installation-bundle/src/Event/InitializeApplicationEvent.php:20 Stack trace: #0 {main} thrown in /home/likach/contao44.lika.ch/vendor/contao/installation-bundle/src/Event/InitializeApplicationEvent.php on line 20