Fatal error: Uncaught Error: Interface 'Symfony\Component\EventDispatcher\EventSubscriberInterface' not found in /home/eberhardschwarze/public_html/vendor/nelmio/security-bundle/EventListener/XssProtectionListener.php:23 Stack trace: #0 {main} thrown in /home/eberhardschwarze/public_html/vendor/nelmio/security-bundle/EventListener/XssProtectionListener.php on line 23