Firefox uses a base app for its Flatpak build that supplies dependencies for the final Flatpak.

Currently, the Flatpak implementation of Thunderbird reuses this base app. However, notification sounds may not work in Thunderbird when using Firefox's base app, so we should create our own base app that supplies the necessary dependencies for notification sounds.

I find it hard to believe that something is missing from the Firefox base app that Thunderbird would require to produce sound. Before going down this rabbit hole, please identify what is missing.

Thunderbird CI builds against the exact same Debian 8-based sysroot as Firefox. This is done to avoid problems with library versions and such.

It's extremely unlikely that Thunderbird is doing something that different with sound.

In order to play notifications sound on linux desktop thunderbird requires two runtime (not build time) dependencies: libcanberra and sound themes[1] which aren't available in flatpak base runtimes[2] therefore need to be brought within app.

In theory firefox would need them as well, the question is - does firefox have functionality of playing notifications sounds at all? After brief look at its prefs I couldn't find anything about that.

Considering above - if notifications sounds are relevant for ff as well then those two deps can be added to ff base app (I can help with that) and tb could reuse it but if they aren't then adding dependencies which ff don't use may be controversial. In such case separate tb base app may be necessary on flathub.

[1] https://github.com/flathub/org.mozilla.Thunderbird/pull/179

[2] https://gitlab.com/freedesktop-sdk/freedesktop-sdk/-/issues/998

There are several built-in sounds in nsISound.idl as well as provision for playing arbitrary sound files, but I haven't looked into whether any of that is consumed inside FF or if we're the only ones using it.

There seems to be a few cases in Firefox - https://searchfox.org/comm-central/search?q=nsISound&path=&case=false&regexp=false - see browser/ and toolkit/ dirs.

(In reply to Emerson Bernier from comment #2)

In order to play notifications sound on linux desktop thunderbird requires two runtime (not build time) dependencies: libcanberra and sound themes[1] which aren't available in flatpak base runtimes[2] therefore need to be brought within app.

In theory firefox would need them as well, the question is - does firefox have functionality of playing notifications sounds at all? After brief look at its prefs I couldn't find anything about that.

Considering above - if notifications sounds are relevant for ff as well then those two deps can be added to ff base app (I can help with that) and tb could reuse it but if they aren't then adding dependencies which ff don't use may be controversial. In such case separate tb base app may be necessary on flathub.

[1] https://github.com/flathub/org.mozilla.Thunderbird/pull/179

[2] https://gitlab.com/freedesktop-sdk/freedesktop-sdk/-/issues/998

As far as libcanberra goes, it appears there is some recent activity surrounding this on the Firefox side of things with bug 1662970.

The: Gtk-Message: Failed to load module "xyz"

is harmless warning shown in flatpak apps due to leaking host config and this bug report and its duplicates was about those warnings not missing functionality (also recent activity is just bug triaging). I proposed to silence them long time ago[1]

The same warning is shown for current flathub Thunderbird which DOES have working libcanberra so it's unrelated to this issue

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1662970#c2

The patch I wrote for Bug 1825842 eliminates the need for a Base App specific to Thunderbird, as it fixes notification sounds for the Thunderbird Flatpak. Now that it has landed, this bug can be closed.