Fatal error: Uncaught Error: Class "League\OAuth2\Client\Provider\AbstractProvider" not found in /opt/lampp/htdocs/forum/flarum/vendor/omines/oauth2-gitlab/src/Provider/Gitlab.php:28 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/forum/flarum/vendor/omines/oauth2-gitlab/src/Provider/Gitlab.php on line 28