Bug#931068: zenity: Window icon is not displayed under Wayland

[Simon McVittie]

On Thu, 19 Nov 2020 at 21:07:00 +0100, Yvan Masson wrote:
> On Tue, 25 Jun 2019 17:00:15 +0100 Simon McVittie <smcv at debian.org> wrote:
> > - GNOME Shell 3.30 in Xorg mode: chosen icon appears in top bar and dash
> >   (sidebar in overview)
> > - GNOME Shell 3.30 in Wayland mode: a "broken image" icon appears instead
> 
> The results you describe are exactly what I experienced. The issue is still
> here with zenity 3.32.0-6 and Gnome 3.38.1-2.
> 
> As you suggested, I checked with another desktop environment, KDE Wayland
> (using KDE Neon: plasma-desktop 4:5.20.3-0xneon+20.04+focal+build16 and
> zenity 3.32.0-5): the issue is exactly the same. It works on X11 but not on
> Wayland.
> 
> Do you want me to report this upstream?

If you want to pursue this then upstream is the right place, but I don't
think this is necessarily going to be fixable. An arbitrary --icon-name
option made sense in an X11 world, but doesn't really make sense in the
more app-oriented Wayland world view.

In Wayland, as far as I'm aware, the mechanism is that trusted/non-sandboxed
applications can tell the compositor (e.g. GNOME Shell or Plasma Desktop)
what they claim their freedesktop.org app ID is, and if they do, the
compositor will show whatever icon matches that app ID. Zenity can
either say that it's something like "org.gnome.Zenity", or leave it
unspecified and hope the compositor has a good heuristic, but
`zenity --icon-name=edit-copy` doesn't really get to say "I'm whatever
app has edit-copy as its icon".

(Sandboxed applications, like Flatpak apps, don't even get to specify
their own app ID - the compositor can get it directly from Flatpak,
and should ignore whatever the app tries to say, at least under GNOME
Shell - but that doesn't apply in this case.)

Having an option for "tell the compositor your app ID is..." might be a
more achievable upstream feature request than making --icon-name work
under Wayland?

    smcv