I also have trouble keeping mac windows where I left them with external displays attached. I invested $15 in stay https://cordlessdog.com/stay/ https://cordles

I also have trouble keeping mac windows where I left them with external displays attached. I invested $15 in stay https://cordlessdog.com/stay/ https://cordlessdog.com/stay/ I would not say the problem is solved (it's not going to solve artifacts, etc), but it helped me.