1817536 - Some Videos can Autoplay even when Firefox is set to Block Audio & Video

Status: RESOLVED INVALID

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

Description

[BoffinBrain]

Attachment: LaptopMagVideoAutoPlaying.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/111.0

Steps to reproduce:

1. Make a new browser profile and in settings, set Autoplay to "Block Audio & Video".
2. Visit a site like https://www.laptopmag.com/reviews/samsung-galaxy-book-3-pro-360
3. Scroll down until you see the 'Recommended Videos For You' section and the video preview loads.
4. Pretend to do other 'user activity' things like switching tabs, clicking on the page, scrolling the page, switching away from Firefox and back again. (I'm not sure exactly what triggers it yet but I've provided an example video.)

Actual results:

The video eventually autoplays.

Expected results:

Video should never have played.

Additional notes:

I'm not sure if this autoplay is happening after a certain amount of time has passed or when a trusted event such as mouse click has occurred. I'm also not entirely sure what the intended scope of autoplay blocking is supposed to be, so it would be nice for a dev to confirm that.

The framework used to play the video is called JWPlayer.

I was able to reproduce in 110.0 111.0b2.

Comment 1

[BoffinBrain]

Attachment: Capture.mp4

Comment 2

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

The Bugbug bot thinks this bug should belong to the 'Core::Audio/Video: Playback' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 3

[C.M.Chang[:chunmin]]

Hi BoffinBrain, thanks for the report! I can reproduce this on my MacBook Pro by:

1. opening https://www.laptopmag.com/reviews/samsung-galaxy-book-3-pro-360
2. switch to another tab
3. click a blank space on https://www.laptopmag.com/reviews/samsung-galaxy-book-3-pro-360
4. switch to another tab again
5. switch back to https://www.laptopmag.com/reviews/samsung-galaxy-book-3-pro-360

Hey Alastor, can you take a look?

Comment 4

[Ina Popescu, Desktop QA]

I've reproduced also the issue using the latest Nightly 112.0a1 and Firefox 110.0 on Windows 10 x64 and Ubuntu 22.04.
Setting as NEW.

Comment 5

[Alastor Wu [:alwu]]

In our default blocking autoplay policy, Firefox only blocks autoplay before a page get activated by user gestures (eg. click), which means after clicking on the page, Firefox won't block any autoplay then. See here for more details.

Comment 6

[BoffinBrain]

OK, thanks for explaining the defined behaviour. That makes a lot more sense now.