Affected versions

• DevEdition 66.0b1 (20190121133415)
• latest Nightly 66.0a1 (2019-01-21)
• Firefox 45.3.0esr
• Firefox 65.0 RC

Affected platforms

• Windows 7 x64
• Windows 10 x64
• Ubuntu 18.04 x64

Steps to reproduce

1. Go to the following mp4 sample: http://distribution.bbb3d.renderfarming.net/video/mp4/bbb_sunflower_2160p_60fps_normal.mp4

Expected result

• The video is loaded and played back correctly.

Actual result

• The video is jerky.

Regression range

• This is not a recent regression since the issue is reproducible in Firefox 15.0a1. I will determine if this is a regression ASAP.

Additional notes

• We reproduced the issue on machines with NVIDIA GeForce 210 and ATI Radeon 3000.
• Please see about:support details in the "aboutSupport.txt" attachment.

Jean-Yves, any thoughts on who should take a look at this?

I think this is NOT a regression since the issue is reproducible in Firefox 21 (which is the first build where video is played in Firefox browser without using VLC web plugin or another third-party application). In Firefox 15.0a1, the issue is reproduced, but the video is opened using VLC web plugin.

The issue is also reproducible using Firefox 67.0a1 (20190315093917) and 60.6.0esr (20190313191546) on macOS 10.14 using the 3d 4k video where massive stuttering appears when playing the video.

This issue is also reproducible on Ubuntu 16.04 when using the latest Nighlty 71.0a1 (20190912215412).

If this is still an issue it would be useful to capture a profile in Nightly with the Firefox profiler + the Media preset, then to share it and post the link on this bug.