Fatal error: Uncaught Error: Class "Symfony\Component\Yaml\Exception\RuntimeException" not found in /opt/lampp/htdocs/forum/flarum/vendor/symfony/yaml/Exception/DumpException.php:19 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/forum/flarum/vendor/symfony/yaml/Exception/DumpException.php on line 19