Fatal error: Uncaught Error: Class "Drupal\Core\Controller\ControllerBase" not found in /home/fnbrshareacopy/public_html/modules/contrib/block_class/src/Controller/BlockClassController.php:19 Stack trace: #0 {main} thrown in /home/fnbrshareacopy/public_html/modules/contrib/block_class/src/Controller/BlockClassController.php on line 19