Fatal error: Uncaught Error: Interface "Zend\Feed\Reader\ExtensionManagerInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Component/Bridge/ZfExtensionManagerSfContainer.php:14 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Component/Bridge/ZfExtensionManagerSfContainer.php on line 14