1595462 - If a page contains a large number of videos they will all fail to play

Status: NEW

(Core :: Audio/Video: Playback, defect, P3)

Description

[u650909]

Sometimes videos just crash and no longer play unless the torbrowser is restarted and this happens at random

This happens on facebook , youtube and twitter

It can be reproduced by scrolling down this link

​https://twitter.com/search?f=videos&vertical=default&q=cats&src=typd

First few search results will be fine but keep scrolling down and videos will crash and cant play them

Affected: Firefox 68.2.0esr on Debian sid, with no add-on enabled.
Could be also affected: Current stable + nightly builds

Reference:
https://trac.torproject.org/projects/tor/ticket/32448
https://redmine.tails.boum.org/code/issues/17175

Comment 1

[:Gijs (he/him)]

Why is this marked as a security issue?

Comment 2

[u650909]

please choose the right component for this as I didnt change the default

Comment 3

[Alex Chronopoulos [:achronop]]

Can you please add one or more crash reports of this issue. You can find them in about:crashes.

P.S. the reporter has blocked requests, no option to NI him/her.

Comment 4

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

It's not clear to me what is meant by reporter here, so we could use some follow up.

I think what the issue is here is not that the browser is crashing, but that videos stop playing back. I'm going to update this bug assuming that is correct. I'm basing this on

Sometimes videos just crash and no longer play unless the torbrowser is restarted and this happens at random

which makes more sense if it's just the videos that stop, rather than the whole browser.

I can repro this in nightly.

This doesn't appear sec related to me (we still have some whiteboard items set). I'm not sure if they're overloaded in some way because this bug has a tor counterpart. I'm going to clear these, but please let me know if I shouldn't have.

Comment 5

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: TwitterVideoStoppedWorking.png

Adding my own STR.

STR:

• Navigate to https://twitter.com/search?f=videos&vertical=default&q=cats&src=typd
• Scroll down until you see videos/tweets show as in the attached image. Scrolling faster may help repro, which I did by holding page down
• Scroll back upwards and notice that videos that were formally playing are now not

Expected result:
All videos continue to play

Further notes:

• Appears to happen regardless of autoplay settings.
• Does not seem like a regression (went back as far as 2016-11-10 and can repro).
  • I had to open the page in private browsing on some older versions of Firefox to get served the same version.
• Based on original report this affects multiple sites, could be an issue with endless scroll style sites? I've only reproed on twitter.
• I don't need to restart the browser to have videos load again, just reload the page (possibly different from original report?).

Comment 6

[Paul Adenot (:padenot)]

Would be good to have media decoder logs for this.

Comment 7

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Video of bug taking place

Comment 8

[Greg Kindel]

Try uninstalling uBlock and clearing the browser cache.

Comment 9

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

(In reply to Greg Kindel from comment #8)

Try uninstalling uBlock and clearing the browser cache.

I'm able to reproduce on a fresh install without any addons. Enabling or disabling the tracking protection in base Firefox does not seem to have an affect. Are there any specific behaviour that is expected to trigger this (for example, add blocking)?