Fatal error: Uncaught Error: Class "Drupal\Core\Condition\ConditionPluginBase" not found in /home/www/drupal8/test/modules/webform/src/Plugin/Condition/Webform.php:26 Stack trace: #0 {main} thrown in /home/www/drupal8/test/modules/webform/src/Plugin/Condition/Webform.php on line 26