Mirror a monitor to another

[Balint66]

Hi!
I really love niri, that's my main wm that I use daily. Sadly, I can't fully move away from gnome, because right now mirroring the "primary" display to my "secondary" is not possible in niri.

I've tried to use wl-mirror to put it on the other display, but when that window loses focus, it stops updating.

I think it would be really cool, if there were an option to mirror a display to another, or an action to do this, without relying on an external tool.

[YaLTeR]

I agree it would be useful, but display mirroring is somewhat complicated. Also would require thinking how to configure it.

I've tried to use wl-mirror to put it on the other display, but when that window loses focus, it stops updating.

Maybe there's a way to make it work? It sounds like it should work for that case.

[Balint66]

Sadly, it does not work.
The window just freezes after a second or two. I think it has to be something about the backend it's using. It tries to use the dmabuf backend, but because that protocol is missing, it falls back to the screencopy backend.
An xdg-portals backend is in progress, but it's far from usable.

[Balint66]

So, OBS with same backend works. This is pretty weird.

[YaLTeR]

We support both shm and dmabuf for screencopy, and only dmabuf for the portal.