1847416 - Flickering while watching Video on macOS

Status: RESOLVED DUPLICATE of bug 1847087

(Core :: Widget: Cocoa, defect)

Description

[Skye]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/116.0

Steps to reproduce:

• Open Firefox (Stable or Nightly)
• Play a YouTube Video (Windowed and Fullscreen both affected.)
  • Haven't tested with many platforms, but it appears to affect Twitch.tv as well.

System Information:

• macOS Sonoma 14.0 Developer Beta (23A5301h)
• MacBook Pro 16" - M1 Max/32GB/1TB
• Secondary display connected (3440x1440@75Hz Ultrawide)

Actual results:

Video player has a consistent quick light flicker every second or less, content doesn't appear to have any visual artifacts expect for a small flicker. (Video attached for visualisation.)

Expected results:

Video should play as normal.

Comment 1

[Skye]

Attachment: output.mp4

It's a bit compressed to fit, but if a higher quality example is needed let me now :)

Comment 2

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

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