[icedigger]

Is there a way to make programs open up on a certain monitor when opening?

Example:  When opening Firefox have it automatically open up on monitor 2 or 3 instead of monitor 1 and have it stick?

Video card if it matters AMD Radeon Pro WX 7100

[Searchernow]

As far as I can see there is in effect only "one monitor" -

you can choose to mirror , i.e. have the same everything on both monitors,

or in Settings>Display>"Choose This Monitor" for both monitors (with one selected as Primary monitor) then you have a single display across both, i.e. you can drag Firefox etc. from one monitor to the other. Maybe this would give you what you want?

What I do is have Firefox & Documents etc. in Workspace 1, Email client in Ws 2, Brave browser on Ws 3..... add workspaces as needed. I usually close all apps manually before closing down, but you might get it to work without doing that.

[valtam]

Look into devilspie2 or wmctrl from a Google search.

[DeepThought]

I have a dual monitor set up and tbh I don't do anything special but I have a few programs that open on specific monitor.
The monitors are set up as one screen, i.e. the mirror box is unticked in display settings.

All I do is open a program and then drag it to the specific monitor, then I maximise it.

From then on I just close it when finished with and reopen and it remembers it's position and opens on the same monitor.
This "memory" also seems to survive a reboot.

Hope it helps