1686908 - A 1 pixel of line shows under video especially on youtube videos. (Only happening on M1 Macbook, with it's display)

Status: RESOLVED DUPLICATE of bug 1634920

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

Description

[djraymond1]

Attachment: When you look closely under the video, you can see the problem.

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11.1; rv:84.0) Gecko/20100101 Firefox/84.0

Steps to reproduce:

1. Install Firefox on Apple Silicon Macbook (For me, M1 Macbook Air) / It didn't reproduce on 15inch Macbook Pro Intel Model)
2. Go into Youtube, and play any video that contains any color changing/movements. (It doesn't effect on fully one color video)

Actual results:

Underside of video, 1 line of pixels shows up and doesn't move.
The color of it is from video.
It is half size long of video.

Expected results:

It should not show up like this.

Comment 1

[djraymond1]

Attachment: Also Attaching great example why this is a problem.

Comment 2

[djraymond1]

It Looks like think this only happens on Zoomed mode.
on full screen mode or not zoomed, I think it doesn't happen.

BTW I think this isn't my mac's problem, because I got 2 same Macbook Airs and both have same this problem.

Comment 3

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

This sounds like bug 1634920 and like the issue is affecting new and old Macs. I'm going to dupe this against that bug so we can track these issues in a single place.