Fatal error: Uncaught Error: Interface "Symfony\Component\Serializer\Normalizer\NormalizerInterface" not found in /var/www/crm_killing_ninja/core/backend/MediaObjects/Services/PrivateMediaObjectNormalizer.php:37 Stack trace: #0 {main} thrown in /var/www/crm_killing_ninja/core/backend/MediaObjects/Services/PrivateMediaObjectNormalizer.php on line 37