Issue on meet.jit.si: video disappearing on Firefox due to alleged bandwidth congestion

[onlyjob]

This issue started to affect meet.jit.si few weeks ago.

For few years, I've been having two different weekly meetings with usual participants, so our familiarity with Jitsi is high.
(Thank you for such useful and reliable service!)

Few weeks ago, during meetings we all noticed frequent video disappearance (e.g. "video disabled to save bandwidth"), causing video feed to stop then start again sporadically, many times, regardless of performance settings.
I'm on high-performance low-latency network that we have monitored and I could not detect any problems.
I always use Firefox, so as an experiment I tried Chromium and issue completely disappeared.
It was not a one time thing, and the problem persisted over few weeks being reliably reproducible (even from different computers): video sporadically disappears in Firefox but not in Chromium.

This is a regression, as formerly Jitsi was working very well in Firefox.

[damencho]

As an experiment you can try running the previous version of Firefox. Do you still reproduce with it?
There were no significant changes in jvb in the last few weeks that were released on meet.jit.si.

[onlyjob]

I can't... I'm on Debian "stable", running current version of firefox-esr package (just updated again to 102.5.0esr-1~deb11u1 version). It has been updated several times lately, fixing some CVEs. Old(er) versions are no longer available.

Over the weekend, I will try current version of Firefox again, and report if there are any changes.

[damencho]

So you say there was no major Firefox update for this period that you are talking about?

[onlyjob]

Let's see (this is from aptitude changelog firefox-esr):

firefox-esr (102.5.0esr-1~deb11u1) bullseye-security; urgency=medium

  * New upstream release.
  * Fixes for mfsa2022-48, also known as:
    CVE-2022-45403, CVE-2022-45404, CVE-2022-45405, CVE-2022-45406,
    CVE-2022-45408, CVE-2022-45409, CVE-2022-45410, CVE-2022-45411,
    CVE-2022-45412, CVE-2022-45416, CVE-2022-45418, CVE-2022-45420,
    CVE-2022-45421.

  * debian/rules:
    - Use internal libevent on buster.
    - Invoke python with PYTHONDONTWRITEBYTECODE instead of -B.

  * ipc/chromium/src/third_party/libevent/linux/event2/event-config.h,
    toolkit/crashreporter/client/ping.cpp: Avoid build bustage when
    building against glibc 2.36 or newer. bz#1782988.

 -- Mike Hommey <glandium@debian.org>  Wed, 16 Nov 2022 06:20:30 +0900

firefox-esr (102.4.0esr-1~deb11u1) bullseye-security; urgency=medium

  * New upstream release.
  * Fixes for mfsa2022-45, also known as:
    CVE-2022-42927, CVE-2022-42928, CVE-2022-42929, CVE-2022-42932.

 -- Mike Hommey <glandium@debian.org>  Wed, 19 Oct 2022 05:04:39 +0900

firefox-esr (102.3.0esr-1~deb11u1) bullseye-security; urgency=medium

  * New upstream release.
  * Fixes for mfsa2022-41, also known as:
    CVE-2022-40959, CVE-2022-40960, CVE-2022-40958, CVE-2022-40956,
    CVE-2022-40957, CVE-2022-40962.

 -- Mike Hommey <glandium@debian.org>  Wed, 21 Sep 2022 06:58:15 +0900

I'd say probably 102.4 and 102.3 are affected, not sure about 102.5 yet.

[onlyjob]

On 2022-09-25, firefox-esr have been updated from 91.13.0esr-1~deb11u1 to 102.3.0esr-1~deb11u1. Maybe it started then...

[onlyjob]

With 102.5.0 this issue is almost non-existent. We've observed only several incidents of temporary video loss ("to save bandwidth") over few-hours long meeting. Definitely better now. However, there was a time when this issue did not exist at all...

[saghul]

I'd say we close this as a browser issue.

[onlyjob]

No, this issue should not be dismissed lightly, unless you think that is is "OK" to ignore a problem in the second world's most common browser.

Yesterday I had a long meeting with quite an unpleasant experience of permanently disappearing video again.
We did some tests and found that the worst combination is Firefox-Chromium, slightly better Firefox-Firefox and flawless with Chromium-Chromium. That definitely looks like a bug to me, when the same network conditions cause spurious video issues with up-to-date Firefox.

I hope you might be able to reproduce the problem with Firefox-Chromium combination of browsers. Thanks.

[saghul]

@nils-ohlmeier Are we aware of any BWE shenanigans with FF?

[tguruswamy]

I see this (unexpected BWE on formerly reliable setup, same peers via meet.jit.si) with Firefox 107.0 on Linux (openSUSE Tumbleweed).

Bandwidth estimation shows N/A: N/A

[onlyjob]

I had another incident on Firefox/102.5: joined a usual meeting and was advised that my video is "disabled to save bandwidth". It was not possible to tell if anything was wrong from my end. Had to join from Chromium and we had no issues for hours.

Firefox just updated to 102.6.0esr so I'll report if that changed anything in few days.

[onlyjob]

Ever since my last comment here, this issue manifested every week on every minor release of Firefox ESR.
I'm currently using 102.12.0esr (64-bit) version on Debian 12 "bookworm" and video intermittently switching off ("to save bandwidth") then coming back on within a minute or so, only to disappear again shortly.

Is there hope that this issue will be eventually fixed?

P.S. Video still works flawlessly in Chromium.

FYI @TFBW

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[tguruswamy]

Still observing this issue in Firefox 117.0, Windows and Linux.

[spluess]

Also still observing with FireFox 117.0.1 on Mac, Windows and Linux. Guess we might need to re-open this one or create a new issue.

[damencho]

Do you reproduce it with FF 116?

[onlyjob]

Debian have Firefox 115.3.0esr at the moment. I've used it once with Jitsi and it looks like situation have improved, however video disappeared once, and came back automatically several seconds later. (Formerly video would either not restore or restore after a while). In Chromium this problem don't manifest at all.

I'll test more with 115.3.0esr over the weekend and report.