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