I just had a brain fart when switching from one tab (or window!) in my browser. Same scenario. We evolved to use this to be best able to: hunt, forage, socialise etc.

I was one of the first people in Britain to use a windowing system for work, and my brain found a neat way of coping. I started having dreams that were in panels, so I could switch from one dream to another while inside a sort of meta-dream.