Fatal error: Uncaught Error: Interface "Twig_LoaderInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Template/Loader/StringLoader.php:23 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Template/Loader/StringLoader.php on line 23