The image appears skewed as if the stride is off. I believe I may have seen this before briefly while watching tests but it seemed intermittent. I thought it was happening during screen sharing, but it looks to be happening during window sharing only (at least at the moment).

I see similar tearing when taking a screenshot using Bugzilla's screenshot tool:

Steps to reproduce:

1. In this Bugzilla bug report, click the "Attach New File" button.
2. On the "Create New Attachment" page, click the "take a screenshot" link.
3. In the door hanger, select a window (NOT "Entire screen").

Result:

The screenshot image's stride is wrong. See the attached screenshot.

I bisected this regression to this pushlog containing libwebrtc update bug 1654112:

https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=c8fdcf75317d40a3ead539a959f748c940d0a5c9&tochange=1495ca5ef535f8ad692a3a579ca42eddc14f39a8

[Tracking Requested - why for this release]:

This is a bad regression in Firefox 96 from libwebrtc update bug 1654112.

I have only tested on Windows 11.

There's a patch up on bug 1738946 so let's use that.