1876502 - Screen sharing stopped working in version 122

Status: RESOLVED DUPLICATE of bug 1875201

(Core :: WebRTC, defect)

Description

[Julien Palard]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:122.0) Gecko/20100101 Firefox/122.0

Steps to reproduce:

• Open a screen sharing thing (tried Jitsi and Big Blue Button), for example: https://video.le-filament.com/firefox-bug
• Open it also in a another tab, or another computer (I used a private tab, Ctrl-shift-P).
• Share your screen, from one of them, to the other.

Actual results:

The screen is not shared: there's no video in the other side.

Expected results:

A video of the screen should be visible on the other side.

It's happening on Debian sid, right after the upgrade from the firefox Debian package from 121.0.1-1 to 122.0-1:

$ apt-cache policy firefox
firefox:
  Installé : 122.0-1
  Candidat : 122.0-1
 Table de version :
 *** 122.0-1 500
        500 https://deb.debian.org/debian sid/main amd64 Packages
        100 /var/lib/dpkg/status

I remember using screen sharing on 2024-01-23, before the upgrade to firefox 122, and it was working.

I tried reinstalling Firefox 121, but sadly I don't have it in /var/cache/apt/.

I tried reinstalling Firefox 120 via sudo dpkg -i /var/cache/apt/archives/firefox_120.0-2_amd64.deb and screen sharing do work with this version.

I tried re-upgrading via apt upgrade, got firefox 122 back, and screen sharing is broken again.

I do use Firefox from Debian sid but I otherwise use packages from Debian Trixie, so I'm using pipewire 1.0.1-1, gnome 44, wayland.

Comment 1

[Julien Palard]

In qpwgraph I do see "gnome-shell [meta-screen-cast...]" → "firefox [webrtc-consume-stream]".

I don't really know how to diagnose this further, don't hesitate to ask me.

Comment 2

[Julien Palard]

https://webrtc.github.io/samples/src/content/getusermedia/getdisplaymedia/ does work though.

Which is not surprising, in Jitsi and BBB the "local preview" of the screen sharing do work, it's just "not sent" or something like this.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Fenix::General' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 4

[Julien Palard]

I tried mozregression, but it always works, maybe it has to do with some Debian build things?

Comment 5

[jackyzy823]

I think bugbot moves this to the wrong components.

Comment 6

[Hanabishi]

WebRTC screen sharing is broken in FF 122 Linux version. It did work back in FF 121.

I use Wayland + KDE desktop portal, and there is no portal window appears now. I.e. FF does not even attempt to start sharing.

Btw, Mozilla has its own testing page for that: https://mozilla.github.io/webrtc-landing/gum_test.html

Comment 7

[Julien Palard]

https://mozilla.github.io/webrtc-landing/gum_test.html works on Firefox 122.0 on Gnome/Wayland on Debian, yet the stream is "not sent" to the remote so it is not usable in Jitsi and BigBlueButon.

It looks like this: https://mdk.fr/x/Capture%20d%E2%80%99%C3%A9cran%20du%202024-01-26%2010-42-51.png

It's two Firefox tabs:

• On the left I screenshare, and screen capture is working, we see the "infinite-recursion-screen-capture", so locally it works.
• On the right I join the room, I see "Fellow Jitster's screen" but it does not contain the video of the captured screen, so the screen capture is "not sent" to this client.

It may look like a Jitsi bug, but I don't think it is:

• I see the exact same behavior on Big Blue Button
• If I downgrade Firefox below 122 it works again
• If I upgrade Firefox to 122 is breaks again.

Comment 8

[Julien Palard]

Same behavior on talky.io:

https://mdk.fr/x/Capture%20d%E2%80%99%C3%A9cran%20du%202024-01-26%2010-50-20.png

Comment 9

[Julien Palard]

With a Firefox 122 downloaded from mozilla.org it works, so it has to do with the Debian builds.

Comment 10

[Hanabishi]

Hmm, no. The official binary from Mozilla website doesn't work for me either.

Comment 11

[Hanabishi]

Actually I tested 120 and 121, but neither of them working now too. That's weird.

Seems like this is not a FF codebase issue after all. Maybe some external component update causing the problem.

Comment 12

[Julien Palard]

Looks like we're just not reporting the same issue :)

Comment 13

[Julien Palard]

Tested with Debian's Firefox using a new profile: does not works.

Comment 14

[Julien Palard]

Cross-linking Debian bug : https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1061495

Comment 15

[Julien Palard]

Maybe a duplicate of https://bugzilla.mozilla.org/show_bug.cgi?id=1875201

Comment 16

[Hanabishi]

(In reply to Julien Palard from comment #12)

Looks like we're just not reporting the same issue :)

Yes, nevermind. Turns out it was a weird KDE xdg-desktop-portal problem. After I fixed it, FF 122 starts the screen sharing just fine, the test page works.

But I can kinda confirm your issue now. Using https://video.le-filament.com/ I can see local video stream on the host side, but it is a black screen on the other side.
Using official firefox binary does not help it though.

Comment 17

[Hanabishi]

Actually nvm again, I managed to get it to work. Now it works for me regardless of the package used. I'm not on Debian though.

Also tested on Discord - all fine.

Comment 18

[Andreas Pehrson [:pehrsons]]

If you see the screen share locally it's not a screen sharing issue. I agree bug 1875201 seems like a plausible suspect.

Comment 19

[Jim Mathies [:jimm]]

The fixes for bug 1875201 landed this morning, and should be in tomorrow's nightly builds. If you can please confirm the issue is addressed there. We plan to uplift those fixes to current beta.