Fatal error: Uncaught Error: Class "Symfony\Component\EventDispatcher\EventDispatcher" not found in /home/vincent/http/concrete5/concrete/vendor/symfony/event-dispatcher/ContainerAwareEventDispatcher.php:27 Stack trace: #0 {main} thrown in /home/vincent/http/concrete5/concrete/vendor/symfony/event-dispatcher/ContainerAwareEventDispatcher.php on line 27