On Sat, 29 Nov 2025 at 19:34:27 -0500, Jeremy Bícha wrote:
I can reproduce this issue in Debian Testing, but I can't reproduce
this issue after downgrading systemd back to 258.1-2.
See also the upstream GNOME issue:
https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/8866
This also affects the mechanism that communicates themes via Xsettings.
An easy way to see it is to run a GTK 2 application such as gmpc, in a
GNOME Wayland desktop session, with the gnome-themes-extra package installed.
Bad result: GTK 2's ugly internal default theme, "Raleigh"
(Windows-95-inspired, with thick pseudo-3D bevels)
Good result: GNOME's Adwaita theme, looking superficially similar to GTK
3 or 4
Workaround: systemctl start --user gnome-session-x11-services-ready.target
Unlike the failure mode involving scaling, reproducing the problem this
way this does not require a highDPI display.
GNOME upstream says:
The services behind that target should only be started when Xwayland is
running. Indeed, starting the services unconditionally would result in
Xwayland being launched as well, even if no actual X11 client is running.
That is why it isn't started automatically by systemd.
If an X11 client is started, mutter launches Xwayland and emits a
signal. In response to that signal, gnome-shell asks systemd to start
the unit.
So that must be where the bug is after all, either mutter doesn't emit
the signal, or gnome-shell fails to start the systemd target.
Given Jeremy's observation that this worked with 258.1-2 but doesn't work
with 259~rc1, presumably there must have been a behaviour change in
systemd that changed how this happens. This could either be a systemd
bug, or a gnome-shell/mutter bug that happens to have been harmless
until now.
smcv
