Add PiP selector for a monitor

[Iiridayn]

Is your feature request related to a problem? Please describe.
Monthly I need to open arbitrary .rtf files sequentially from a large collection for display on a monitor I cannot see. I don't want to use screen mirroring as I also would like to take notes in a non-disruptive manner.

Describe the solution you'd like
I would like to see the desktop and all programs running on it in a PiP window.

Describe alternatives you've considered
Best alternative I've found so far is either mirror mode, or sitting where I can see the secondary display, though both have frustrations.

Additional context

[1ucay]

Hi, please, can you add this func?