Fatal error: Uncaught Error: Interface "Composer\Plugin\PluginInterface" not found in /home/rcmch/test.m-s-i.ch/vendor/typo3/class-alias-loader/src/Plugin.php:22 Stack trace: #0 {main} thrown in /home/rcmch/test.m-s-i.ch/vendor/typo3/class-alias-loader/src/Plugin.php on line 22