I had this issue back in Godot 3.5 and hoped that it'd be gone, but Panels and some other Control Nodes still resize magically when executing another scene. This is such weird behaviour, that I have no idea where it might come from. Has anyone ever seen such a thing happen before? Here is a video of the bug in acton: https://piped.kavin.rocks/watch?v=79DYDT5qngk
From a glance, I'd tell you to take a look at the Hbox
Bottom -> Bottomfirst, the one that has both a Control and the BallsCounter. These box container nodes will auto expand to fit all content.An alternative would be scaling that Bottom node, instead of resizing it.