1650616 - flickering of small area of videos on macOS Big Sur Beta

Status: RESOLVED DUPLICATE of bug 1629220

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

Description

[Sören Hentzschel]

On macOS Big Sur Developer Beta 1 there is a flickering when I watch YouTube videos. But not on the whole video, only on one small area and only when you move the mouse over the video and you see the progress and media controls. This didn't happen on the same machine with macOS Catalina.

I made a screencast:
https://www.youtube.com/watch?v=JKb17dg__JY

Comment 1

[maxwell.leiter]

I can confirm a similar/the same issue with Netflix subtitles

Comment 2

[Sören Hentzschel]

Attachment: about:support

I attached my information from about:support.

Comment 3

[Sören Hentzschel]

Based on comment 1 and because I noticed a similar behaviour on a few other websites I removed "YouTube" from the bug summary because it's not a YouTube-only issue but a general video issue.

Comment 4

[u665444]

It seems like the newest nightly build fixed this. At least for me.

Comment 5

[Joe McCabe]

I'm unable to reproduce under Big Sur beta 3 (I'm unsure if this is due to the update to Beta 3 or if a fix landed in a nightly a few days ago as noted in Comment 4).

Comment 6

[Sören Hentzschel]

I can confirm that it no longer happens and that it was already fixed before the update to Big Sur Beta 3. So it seems to be fixed by a Firefox change. But it would still be interesting to know which change fixed this to make sure that it was not accidentally fixed and will be broken in the future again. Unfortunately the current version of the mozregression GUI is completely broken on Big Sur at the moment (bug 1650612). And the mozregression command line tool was already broken for me before the update to Big Sur and I don't have the time to investigate the cause and to fix it. So maybe someone other could run mozregression on the command line to find the fix?

Comment 7

[sorenpearson]

I can confirm this happens for me on MacOS Big Sur Public Beta 1. 11.0 Beta (20A5343j) Firefox version 79.0

Comment 9

[Haik Aftandilian [:haik]]

Is this still reproducible? It may have been a duplicate of bug 1647816 or bug 1655655 which are both fixed in 80. Or it may have been fixed in a more recent macOS 11 Beta. It is no longer reproducible for me on Beta 5 (20A5354i).

Comment 10

[sorenpearson]

(In reply to Haik Aftandilian [:haik] from comment #9)

Is this still reproducible? It may have been a duplicate of bug 1647816 or bug 1655655 which are both fixed in 80. Or it may have been fixed in a more recent macOS 11 Beta. It is no longer reproducible for me on Beta 5 (20A5354i).

Seems to be fixed for me. I'm not able reproduce it in v80 but still running 20A5343j of MacOS Big Sur.

Comment 11

[Sören Hentzschel]

I can no longer reproduce, but I don't know what fixed the issue, see comment 6.

Comment 12

[Markus Stange [:mstange]]

This was fixed by bug 1629220 and by bug 1648836.