Fatal error: Uncaught Error: Interface "Psr\Http\Server\MiddlewareInterface" not found in /opt/lampp/htdocs/forum/flarum/vendor/middlewares/request-handler/src/RequestHandler.php:15 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/forum/flarum/vendor/middlewares/request-handler/src/RequestHandler.php on line 15