Error booting Flarum: Return value of Flarum\Extension\Extension

Hi,
I was installing extensions. Right after I activated some of them, I got this error:

Error booting Flarum: Return value of Flarum\Extension\Extension::getExtenderFile() must be of the type string or null, none returned

Can you help me?

Johnny

mediaforos You most likely installed an extension that isn’t compatible with recent Flarum versions. What extensions did you install ?

datitisev I installed many though. I would not remember which one. I am making a clean copy of the forum.

Johnny

mediaforos You can look at the composer.json to see what packages have been installled, including extensions and Flarum core.

datitisev Thanks! I created a new copy thoug.