Fatal error: Uncaught Error: Class 'Composer\Util\Filesystem' not found in /var/www/typo3/vendor/typo3/cms-composer-installers/src/Plugin/Util/Filesystem.php:21 Stack trace: #0 {main} thrown in /var/www/typo3/vendor/typo3/cms-composer-installers/src/Plugin/Util/Filesystem.php on line 21