Fatal error: Uncaught Error: Class "Drupal\Core\Language\LanguageManager" not found in /home/www/drupal8/test/core/modules/language/src/ConfigurableLanguageManager.php:20 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/language/src/ConfigurableLanguageManager.php on line 20