Fatal error: Uncaught Error: Class 'Symfony\Component\EventDispatcher\EventDispatcher' not found in /home/app/htdocs/ninja/vendor/symfony/event-dispatcher/ContainerAwareEventDispatcher.php:24
Stack trace:
#0 {main}
thrown in /home/app/htdocs/ninja/vendor/symfony/event-dispatcher/ContainerAwareEventDispatcher.php on line 24