Q: Unpredictable resizing of desktop

I unchecked the keyboard shortcuts for zoom, but as I say, this resizing of the desktop takes place when I'm not even seated at the computer. Sure would be nice if this were a fix though! I've never intentionally used zoom shortcuts anyway ........

As I feared, this wasn't the solution. My screen has gone giant twice more since I unchecked the shortcuts. Both times while I was not at the computer ....... a shutdown/unplug the computer still works, perhaps better than a simple restart ...... but I can't say for sure, and there's no way to know how long this will work. Problem is definitely getting worse.