Fatal error: Uncaught Error: Class "Drupal\Core\Block\BlockBase" not found in /home/qcsvlel/www/core/modules/node/src/Plugin/Block/SyndicateBlock.php:28 Stack trace: #0 {main} thrown in /home/qcsvlel/www/core/modules/node/src/Plugin/Block/SyndicateBlock.php on line 28