Fatal error: Uncaught Error: Interface "Psr\Http\Server\MiddlewareInterface" not found in /home/rcmch/test.m-s-i.ch/vendor/typo3/cms-backend/Classes/Middleware/OutputCompression.php:31 Stack trace: #0 {main} thrown in /home/rcmch/test.m-s-i.ch/vendor/typo3/cms-backend/Classes/Middleware/OutputCompression.php on line 31