Fatal error: Uncaught Error: Interface "Drupal\workspaces\WorkspacePublisherInterface" not found in /home/www/drupal8/test/core/modules/workspaces/src/WorkspacePublisher.php:13 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/workspaces/src/WorkspacePublisher.php on line 13