Oh man, I feel for you - I think people in here don't understand. I also work professionally on the newest Macbook, and this is a UX design issue (my profession is UX and UI design, so I actually design software interfaces).
The issue is with Apple and they way they have assumed that people want to have the focus change automatically. That happens for ALL apps that you open, and it's quite unbelievable as a designer of user-friendly systems, that I can't decide for myself if I want the system to do that by itself, without me wanting it. I think it happens mostly to people like us who work and move fast between apps. It's the issue of the system design, not the user. So YES, the system 'steals' focus when it wants to, leaving the user helpless and suddenly writing in another program or having something pop up over your current app when least expected. I was just searching for a fix for this also, since it finally annoyed me too much. No fix found so far
The issue is with Apple and they way they have assumed that people want to have the focus change automatically. That happens for ALL apps that you open, and it's quite unbelievable as a designer of user-friendly systems, that I can't decide for myself if I want the system to do that by itself, without me wanting it. I think it happens mostly to people like us who work and move fast between apps. It's the issue of the system design, not the user. So YES, the system 'steals' focus when it wants to, leaving the user helpless and suddenly writing in another program or having something pop up over your current app when least expected. I was just searching for a fix for this also, since it finally annoyed me too much. No fix found so far