Fatal error: Uncaught Error: Class "Drupal\Core\ImageToolkit\ImageToolkitBase" not found in /home/www/drupal8/test/core/modules/system/src/Plugin/ImageToolkit/GDToolkit.php:23 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/system/src/Plugin/ImageToolkit/GDToolkit.php on line 23