Fatal error: Uncaught Error: Class "Drupal\Core\Condition\ConditionPluginBase" not found in /home/www/drupal8/test/core/modules/language/src/Plugin/Condition/Language.php:23 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/language/src/Plugin/Condition/Language.php on line 23