I have 2 displays, a monitor and a TV. The first one I use all the time and it has set as primary in Gnome settings, but a TV is turned on only when watching movies from a sofa. Mainly, everything is going as expected, but some apps opens at the TV which is turned off at the moment, thus, I have to turn it on and drag window to the monitor and it happens all the time with a certain apps, i.e. qBittorrent.
I spent a lot of time with Google but I failed to find a way to let all apps appear on primary display.