Endless loading and Godot not responding after fixing ignored scenes

[NickHatBoecker]

After https://github.com/maktoobgar/scene_manager/issues/23 was solved (thank you so much for this!), I downloaded the current main branch. I opened my project and got a lot of errors and the scene manager window was empty. I just closed it and reopened it again. Now the errors were gone and the window displayed my scenes.

But I get a loading cursor and MacOS reports the app as "not responding". So I cannot work on the project. I restored the previous version of scene manager I used (3.8.0) and it immediately works again.

Unfortunately no error message is displayed, so I don't know what could cause the problem.