Fatal error: Uncaught Error: Class 'Symfony\Component\Form\AbstractTypeExtension' not found in /home/clapsabo/test/vendor/symfony/form/Tests/Fixtures/FooTypeBazExtension.php:17 Stack trace: #0 {main} thrown in /home/clapsabo/test/vendor/symfony/form/Tests/Fixtures/FooTypeBazExtension.php on line 17