When copying a config menu from one of my projects to the other, I came across something rather unusual. Some objects, when pasted, have no sprites attached, their initial frame becomes -1, and the animation editor for said object is unopenable.
Running the game with this, naturally, crashes the editor, but a simple reload will fix the issue.
Does anyone have any idea as to why this might be occuring? It's not related to family behaviours or instance variables, but ironically the animation names seem to have something to do with this. Animations such as English_On or Chinese_On would have the frame as 0 while English_Off and Chinese_Off would have the frame as -1.
Hopefully this helps someone encountering the same issue, but as I cannot for the life of me repeat the bug, I can only hope that nobody's projects break to this error.