Is it possible to change the size of the UI?

Unfortunately not yet possible. Do you want to make it smaller for  smaller screen or larger for 4k or something?

I have this problem too
When I go to play on the notebook that has a smaller screen than the desktop computer, the other features are missing, due to the smaller screen.

It more like I have to drag around the UI to get to all parts. Like I prepare a schematic but have to drag the menu to save it.