Fatal error: Uncaught Error: Class "Slim\Psr7\Message" not found in /home/rosengar/Lib/composerRosengartPHP8/vendor/slim/psr7/tests/Mocks/MessageStub.php:17 Stack trace: #0 {main} thrown in /home/rosengar/Lib/composerRosengartPHP8/vendor/slim/psr7/tests/Mocks/MessageStub.php on line 17