Open Bug 1650584 Opened 4 years ago Updated 1 month ago

Second monitor - video stutters / lags.


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

78 Branch





(Reporter: lkocik, Unassigned, NeedInfo)



(1 file)

Attached video 2020-07-04 18-36-47.mkv

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Firefox/78.0

Steps to reproduce:

Video stutters / lags on the second monitor while scrolling the pages in the browser (one monitor - firefox browser, the other monitor - running video from another application). Occurs only in the case of Firefox browser - after the latest latest update.

Actual results:

When I run a movie / video in any resolution (be it 1080p, 720p, 30fps, 25, fps, 60 fps) on TV (the second monitor connected to the laptop) and at the same time I use the firefox browser - when scrolling / browsing video websites it starts to lag - frame. I tested on other browsers - the problem does not occur. It started appearing only after updating to the latest version of firefox. Captured problem in attachment - visible frames / jams occur when browsing web pages in firefox.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Component: Untriaged → Audio/Video: Playback
Product: Firefox → Core

It sounds like the performance issue is taking place in another program, is that correct? If that is the case it's going to be highly difficult to diagnose the interaction between Firefox and the other program that lead to the issue. The best bet would be profiling Firefox to see if it's using more resources than expected.

Flags: needinfo?(lkocik)

Just ran into this issue on a M2 Max 16 inch MBP, running Firefox Developer Edition: 124.0b7 and (just updated) 124.0b8. I also tried to reproduce this on a brand new profile and it also happens there - video and audio skips randomly when a youtube video is put on another window on the second monitor (internal monitor). The external monitor and the internal monitor are both running at 120hz (though the external is strict 120hz and the internal one is ProMotion).

I would love to provide more information if needed.

Redirect a needinfo that is pending on an inactive user to the triage owner.
:jimm, since the bug has recent activity, could you have a look please?

For more information, please visit BugBot documentation.

Flags: needinfo?(lkocik) → needinfo?(jmathies)
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