Among the Firefox Wayland bugs, one of the top crash bugs is over a lost connection to a Wayland compositor. For dealing with it is to have a proxy between Firefox and the Wayland compositor to cache messages and prevent compositor message queue overflows.
That sounds more like a compositor problem - typically a client should not have control over where windows are placed, and that X11 allowed that got heavily abused with negative impact on UI. Wayland fortunately fixed that, so it is now up to the compositor where to place windows. Those can send hints, but the compositor is free to ignore them.
In your situation your compositor should remember where to stick the windows.
Kwin. It works with xwayland, doesn’t with wayland, I’d love a solution, but I found nothing.
Window rules based on the application name and window title?
Doesn’t the window title change on firefox depending on tab or even web-page?
Yeah, if you want certain pages in certain screens it would work, and then they’d stay there
And if I ever browse away from that page and forget to return to it before closing firefox…
This has a million caveats and isn’t even close to a solution for how I use firefox. Each desktop has their own windows and I want them to stay there because the tabs open are relevant to that desktop.
Meanwhile forcing xwayland, just works.