1155674 - [Youtube][HTML5] 4k videos are not played

Status: RESOLVED WORKSFORME

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

Description

[Petruta Horea [:phorea], Desktop QA]

Mozilla/5.0 (Windows NT 6.2; rv:38.0) Gecko/20100101 Firefox/38.0
Reproducible on:
 Firefox 38 beta 5 - 20150416143048
 Firefox 37.0.1 and 37.0.2
 latest Developer Edition 39.0a2 2015-04-17
 latest Nightly 40.0a1 2015-04-16 

Steps to reproduce:
1. Go to http://youtube.com and verify that html5 is used when playing videos
2. Search 4k videos (or open https://www.youtube.com/watch?v=lpzCSZ7Eerc)
3. Change video quality to 2160p 4K

Expected results:
Video continues to play at 4K quality

Actual results:
The video cursor is placed at the beginning and the video is not played.
or
The video is played for some seconds (Dev Edition) or minutes (Nightly) and then it stops and the cursor goes at start.
In both cases the following error message is shown in console:
Media resource mediasource:https://www.youtube.com/c8213dc2-071f-4f9f-b974-95c7a8649ec2 could not be decoded.

Comment 1

[Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)]

Is this issue still reproducible?

Comment 2

[Petruta Horea [:phorea], Desktop QA]

Tested several 4K videos using Firefox 42 beta 4, latest Aurora 43.0a2 and Nightlty 44.0a1 under Win 8 32-bit and didn't see the issue anymore.

Closing as RWFM.