Switching alert sound theme doesn't work

[Jeremy Bícha]

Test Case
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1. Open the Settings app.
2. Open Sound then choose a different Alert Sound at the bottom of the page.
3. Open a terminal/console app
4. Press the backspace key.
5. You should hear the chosen Alert Sound

What Happens
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In my case, I always hear the default alert sound.

This issue may have been previous reported in https://launchpad.net/bugs/1871320

In that bug, it seems like switching to the default then to a different alert sound changed the sound.

Other Info
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Ubuntu includes a Yaru sound theme by default. Unlike other themes, Freedesktop.org sound themes are fairly rare in desktop Linux.

The bug seemed to also happen to me if I built gnome-control-center without our sound theme patch.

https://salsa.debian.org/gnome-team/gnome-control-center/-/blob/ubuntu/master/debian/patches/ubuntu/sound-Add-a-button-to-select-the-default-theme.patch

However, this feature did seem to work correctly for me on Debian Unstable even with gnome-control-center 43.

Related Bug
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This feature is broken worse in GNOME 43:
https://launchpad.net/bugs/1987161