Possible issues with background playback of YouTube playlists

[buttercookie42]

Steps to reproduce

1. Install the Video Background Play Fix add-on.
2. Visit a Youtube playlist, e.g. https://m.youtube.com/playlist?list=PL4B22D54E54AC7CB9
3. Start playback.
4. Switch to a different tab.
5. Put Firefox into the background.

Expected behaviour

Playback of the playlist continues successfully across all tracks.

Actual behaviour

I've had some reports (mozilla/video-bg-play#32) that playback gets stuck once it reaches the end of the current track, i.e. playback of the following track doesn't successfully resume.

Personally I tried to reproduce this both in October, as well as now with a current Nightly (2022-12-22 50cc477 is the latest that doesn't crash for me due to #28310), but couldn't, i.e. playback works perfectly fine. There might possibly be a slight additional delay between tracks as compared to foreground playback, but playback of the next track eventually always successfully resumes.

However it's quite possible that the behaviour here is significantly being influenced by the actual Android version and (due to additional manufacturer customisations in that area) specific device.

Device name

No response

Android version

various versions between 10 and 12

Firefox release type

Firefox

Firefox version

current(ish)

Device logs

No response

Additional information

Report 1:

I checked with my Samsung Android 9 tablet, which runs One UI 1.1 and the
background playlists work, though it took literally about a minute. My
Samsung Android 12 phone with One UI 4.1 does not work.

Report 2:

I have the same issue with my LG v35 (android 10) and on a Motorola g52 (android 12 I think). I have the issue on Firefox and Firefox nightly
On my LG I added Firefox to the battery exception list, so in theory android shouldn't throttle the app, so I guess it might be coming from firefox

On my old Motorola G4 Play with Android 6.0.1, things also work perfectly fine.

┆Issue is synchronized with this Jira Task

[cpeterso]

Moved to bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1812957

Change performed by the Move to Bugzilla add-on.