bug#70111: Gnome 44: Dark Theme not Working

[Dariqq]

Hi Guix,

Updated my system to Gnome 44 f5558ee0cc1a11a8b61d3f4d43f05dd79d53ac77 
and the dark style setting in Gnome no longer works (compared to Gnome 
42), i.e. apps like gnome-control-center and nautilus still have the 
light theme even though the setting is set to Dark.

The setting from the control-center is applied correctly:

 guix shell glib:bin -- gsettings get org.gnome.desktop.interface 
color-scheme
'prefer-dark'

"GTK_THEME" is unset, no extra config in ~/.config/gtk-*.0/settings.ini 
and also Application>Appeareance in Gnome Tweaks is set to Adwaita-Dark.

Some results from searching online suggest to install xdg-desktop-portal 
and adding that to the system profile and rebooting indeed makes the 
dark setting work as expected.

Should this be handled by the gnome-desktop-service-type, i.e. added by 
one of the gnome-meta-packages (probably gnome-essential-extras)?

Thanks.