Fatal error: Uncaught Error: Interface "Psr\Http\Server\MiddlewareInterface" not found in /opt/lampp/htdocs/forum/flarum/vendor/franzl/whoops-middleware/src/WhoopsMiddleware.php:13 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/forum/flarum/vendor/franzl/whoops-middleware/src/WhoopsMiddleware.php on line 13