Fatal error: Uncaught Error: Class "Symfony\Component\Serializer\Serializer" not found in /home/qcsvlel/www/core/modules/serialization/src/Serializer/Serializer.php:12 Stack trace: #0 {main} thrown in /home/qcsvlel/www/core/modules/serialization/src/Serializer/Serializer.php on line 12