[snap] Notifications do not show a custom icon

Chromium uses the Desktop Notifications specification¹ to display notifications².
It sets the app_icon parameter, and according to the specification³, « The "app_icon" parameter and "image-path" hint should be either an URI (file:// is the only URI schema supported right now) or a name in a freedesktop.org-compliant icon theme (not a GTK+ stock ID). »

So a file:// prefix is expected, and correct.
Can you share more details on the problem? Maybe use dbus-monitor to watch the notifications coming in, and share the value of the app_icon parameter?

¹ https://developer.gnome.org/notification-spec
² https://source.chromium.org/chromium/chromium/src/+/master:chrome/browser/notifications/notification_platform_bridge_linux.cc;l=582
³ https://developer.gnome.org/notification-spec/#icons-and-images-formats

In other words.

As soon as you use Chromium as a snap, the icons / pictures in notifications are not correct ( usually fallback to a generic one ).

Compare with Chromium on other systems or with other web browser from same website, on the same system.

As mentioned, I'm just a messenger here and quoted the fine people who try to fix this.

My amateur attempt to clairfy... I believe the issue Coeur Noir is referring to is that Raven / Budgie gets this example as the app_icon:

file:///tmp/.org.chromium.Chromium.beVtiT

But due to it being a snap, the file is actually located at:

/tmp/snap.chromium/tmp/.org.chromium.Chromium.beVtiT

Therefore, Raven (Raven / Budgie Desktop) fails to find the correct file.

Whether this is ultimately a Raven issue or a Chromium issue, I don't know.

Could you give an example or testcase?

Trying on a random website, e.g https://web-push-book.gauntface.com/demos/notification-examples/ the notification displays correctly including icons or image on current chromium snap version

Using dbus-monitor, and the test site given ( https://web-push-book.gauntface.com/demos/notification-examples/ )

output:
   string "Chromium"
   uint32 0
   string "file:///tmp/.org.chromium.Chromium.kuprxj"
   string "Web Push Book"
   string "web-push-book.gauntface.com

The file does not seem to exist? Instead, I have:
"/tmp/snap.chromium/tmp.org.chromium.Chromium.kuprxj"
created on my system.

Given that this works on other distros, I am guessing the issue must be with Raven/Budgie handling of the noticfications.

Séb, I can confirm what Sam and coeur-noir are seeing. No icon is displayed on notifications with that example website you linked to, and using dbus-monitor I can see that the icons are being saved under the snap's confined TMPDIR, so the path is not visible from the host.

This would probably need a patch to rewrite the path, or save the temporary icon file to a different place that's visible to the host.

I believe the issue with the Budgie desktop/Raven sidebar might also be mitigated if Raven was changed to fall back to using the browser's icon name (google-chrome, chromium, opera, etc). Currently with a snap, it shows a generic alert icon (not the browser's icon). Probably an issue to be raised at Solus. Would be nice ultimately to see the website's notification image, but I understand the sandboxing of a snap makes things trickier.

As an aside, I notice Brave browser notifications images are visible, using a different path.

image-path: "/run/user/1000/snap.brave/.org.chromium.Chromium.m5lyvv"

Sorry for the confusing, chromium here uses its own notifications and not the system ones which doesn't have the issue described...

Thanks Sam, that's a useful point of comparison.

So the problem here is actually where ( any ) snap will store some files that should be readable by other app's.

No snap can use /tmp by sandboxing design. It's also a problem in Gimp and its plugins for example. Or in Thunderbird when dealing with attached files in mails.

( thumbnails are also a problem in snap as snap can't write into ~/.cache/… )

It seems in Brave case, they found a « better » path ?

Small side comment but Marco did change libnotify to be smart in snaps
https://gitlab.gnome.org/GNOME/libnotify/-/commit/ea61ec43
if chromium doesn't use libnotify then it should probably try to do something similar itself

Chromium doesn't use libnotify, it invokes the org.freedesktop.Notifications D-Bus API directly.

This was also reported upstream: https://bugs.chromium.org/p/chromium/issues/detail?id=1160601.