test.tscn
is the only scene with a button, so I'm assuming that's the one you want us to check.

Well I can immediately see that it's not connected to anything, and there's no script in the scene to use the signal anyway. :/
Edit: After giving it a script and connecting the signals, I now see what you mean. I narrowed down the problem to one of your autoloads (SceneChanger
). Its Control nodes were blocking the inputs.

After setting both Control
and Black
to have a mouse filter mode of Ignore
, the button works fine.