Fatal error: Uncaught Error: Class 'Symfony\Component\Serializer\Serializer' not found in /home/gmcguire/public_html/concrete5/concrete/src/Foundation/Serializer/JsonSerializer.php:7 Stack trace: #0 {main} thrown in /home/gmcguire/public_html/concrete5/concrete/src/Foundation/Serializer/JsonSerializer.php on line 7