1413838 - Camera momentarily turns on, and then permanently off when attempting to use video chat or similar service

Status: RESOLVED WORKSFORME

(Core :: WebRTC: Audio/Video, defect)

Description

[joshua.s.barretto]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:58.0) Gecko/20100101 Firefox/58.0
Build ID: 20171030103605

Steps to reproduce:

I'm running Arch Linux on a Dell Inspiron 15R laptop. Previously, Firefox Nightly has worked perfectly fine with video chat. But since upgrading to v58, video chat no longer functions. This issue occurs when using both Facebook's Messenger and Google Hangouts.


Actual results:

When attempting to start a call, the camera initially lights up to indicate that it is in use. But once the call connects, the light turns off, no video feed shows, and additionally no audio can be heard from the recipient (although I can't confirm that the latter isn't due to an issue on the other end of the call). The microphone still works, however.


Expected results:

Well... Exactly what you expect should have happened. A working video feed and working audio.

Comment 1

[Alex Chronopoulos [:achronop]]

I am on linux and I am able to use my camera. I guess this does not mean anything due to variation in hardware etc. That said, since you can repro there are a number of steps you can take in order to help us find the error:

First check if the camera works on the following test page:
https://mozilla.github.io/webrtc-landing/gum_test.html
Please use "Audio & Video" button. If it works you should see yourself and when you un-mute the audio you should also hear anything you say.

Second and most important please use the mozreview tool:
http://mozilla-version-control-tools.readthedocs.io/en/latest/mozreview.html
That can show as with great accuracy the commit that introduced the error. You run it by providing the working and non working versions, then follow the instructions and after some loops will get it.

Comment 2

[joshua.s.barretto]

(In reply to Alex Chronopoulos [:achronop] from comment #1)
> I am on linux and I am able to use my camera. I guess this does not mean
> anything due to variation in hardware etc. That said, since you can repro
> there are a number of steps you can take in order to help us find the error:
> 
> First check if the camera works on the following test page:
> https://mozilla.github.io/webrtc-landing/gum_test.html
> Please use "Audio & Video" button. If it works you should see yourself and
> when you un-mute the audio you should also hear anything you say.
> 
> Second and most important please use the mozreview tool:
> http://mozilla-version-control-tools.readthedocs.io/en/latest/mozreview.html
> That can show as with great accuracy the commit that introduced the error.
> You run it by providing the working and non working versions, then follow
> the instructions and after some loops will get it.

I've tested my camera with the test page, and it works fine. I think this might be an issue with Facebook Messenger rather than the browser. I've also realised that I'm using an unofficial repository to install Nightly, so I'll switch to the official source and test again.

Comment 3

[Andreas Pehrson [:pehrsons]]

We recently removed `mozSrcObject` (`srcObject` has existed for a good while) in 58, and that at least broke Facebook Messenger (which just deployed a fix btw, so please retest). Interesting if Hangouts is also broken.

Comment 4

[Andreas Pehrson [:pehrsons]]

Joshua, to me the Hangouts issue seems like something else. Can you confirm whether the Hangouts issue you're seeing is activating the camera or not?

Comment 5

[joshua.s.barretto]

Hello all. Sorry about the delay, my life has been busy recently. After investigating this further, I tried reinstalling Nightly from the official repositories. The problem seems to have gone. As Andreas said, that's likely due to Facebook patching the issue rather than the browser being updated. The Hangouts issue seems to have vanished too.