Fix: GDM does not start GNOME Wayland even if it is selected by default, starts X11 instead

[jtojnar]

@uep

Note there’s a deprecation comment on that entry, it seems to have been renamed to services.xserver.displayManager.defaultSession .

Changing the default like this seems like it still might be fragile, if the cause is unknown, though I will add it anyway since it seems to help.

The only thing this does in GDM is setting the preferred session to log into in AccountService. This should be equivalent to selecting it manually in the session chooser.

In the worst case, when GNOME Shell detects problems on startup, it will just fall back to X session regardless the value of services.xserver.displayManager.defaultSession.

But then, the only thing services.xserver.displayManager.defaultSession = "gnome" achieves is that Wayland session will be tried every time. There will not be any guarantee of not falling back on XOrg until the underlying issue (e.g. buggy extension, GPU driver issues, Shell bug…) is resolved.

@uep

Is there a way to not install the X11 session at all?

Not really. You could try patching the appropriate packages to remove the xorg session files but GNOME currently does not support building without X server – Mutter support for that has only just been merged – so if the fallback session were to be not found, it would probably break horribly.