I installed utm-no from @sil to experiment as this snap is tiny and uses the gnome extension. The gnome extension adds plugs for gnome-3-34-1804, gtk-3-themes, icon-themes, and sound-themes. The last three there should all be automatically connected to their relevant slots in the gtk-common-themes snap, but it seems only gtk-3-themes and sound-themes are leaving icon-themes dangling until manually connected.
The non-connected state by default causes, for example, discord to completely crash when calling the add attachment to chat button:
(Discord:1182341): Gtk-WARNING **: 08:29:57.586: Could not load a pixbuf from icon theme.
This may indicate that pixbuf loaders or the mime database could not be found.
**
Gtk:ERROR:../../../../gtk/gtkiconhelper.c:494:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /org/gtk/libgtk/icons/16x16/status/image-missing.png: Unable to load image-loading module: /snap/discord/133/gnome-platform/usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so: /snap/discord/133/gnome-platform/usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so: cannot open shared object file: No such file or directory (gdk-pixbuf-error-quark, 5)
By any chance, do you have theme snaps besides gtk-common-themes installed? If so, which ones?
I think this is a problem with the snap declaration for gtk-common-themes. In particular, there is no slots-per-plug attribute for icon-themes and sound-themes:
I’d missed that this had only been applied to the gtk-2-themes and gtk-3-themes slots. As I understand it, things should connect correctly if gtk-common-themes is the only snap providing an icon-themes content interface slot, but is going to cause problems when a second snap with the slot is installed unless all slot snaps have slots-per-plug: * set.
Interesting. That does sound about right then, because I’m on Ubuntu Mate so I have gtk-theme-yaru-mate included by default out of the box from installation time. (this sentence brought to you by the redundant department of redundancy department)
It’s probably the icon-theme-yaru-mate snap that’s causing the problems (assuming it’s installed). If you remove that snap, I suspect the icon-themes plug should connect correctly when installing snaps.
And to be clear: the problem is in gtk-common-themes rather than the other snaps, and should resolve itself once the snap declaration is updated. I’ve put in a request to update this here:
It looks like I’ve got the new gtk-common-themes assertion after an auto-refresh occurred. You should be able to tell the same on your system by running the following (note no use of --remote):
$ snap known snap-declaration series=16 snap-id=jZLfBRzf1cYlYysIjD2bwSzNtngY0qit
If that shows revision 6 of the assertion, then I would expect auto-connection of icon-themes plugs for newly installed or refreshed snaps to auto-connect correctly. When you’ve got a chance, could you verify if that’s the case for you too?
I got the same error when trying to download a file:
(ferdium:976667): Gtk-WARNING **: 08:54:55.008: Could not load a pixbuf from icon theme.
This may indicate that pixbuf loaders or the mime database could not be found.
**
Gtk:ERROR:../../../../gtk/gtkiconhelper.c:494:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /snap/ferdium/278/data-dir/icons/Yaru/16x16/status/image-missing.png: Unrecognized image file format (gdk-pixbuf-error-quark, 3)
