Fatal error: Uncaught Error: Interface 'Drupal\Composer\Plugin\Scaffold\PostPackageEventListenerInterface' not found in /home/devmecseminars/public_html/mec/vendor/drupal/core-composer-scaffold/AllowedPackages.php:19 Stack trace: #0 {main} thrown in /home/devmecseminars/public_html/mec/vendor/drupal/core-composer-scaffold/AllowedPackages.php on line 19