Well "it" happened again, but I still don't know what caused it. No sleep/wake involved, just seemingly normal work leading up to it.

One interesting aspect is that I had two instances of MoI running. The first (main) instance had my model open while the second was to open a .DXF file of parts that had just been nested (using deepnest.io for what that's worth). I had just copied the nested parts from the DXF instance and pasted into my model when I noticed the main instance was now locked on zoom for the 2-finger gesture. I finished my work and closed the main instance. This morning I noted that the DXF instance was still open and was interested to note that it too had the zoom behavior. Now, the MacBook Pro did sleep overnight and I do not know if it exhibited the zoom behavior before the sleep.

I think the root cause is covid...everybody using zoom & MoI doesn't want to feel left out... ;-}

--Larry