1161902 - YouTube doesn't fall back to Flash when Media Foundation .DLLs are missing

Status: RESOLVED DUPLICATE of bug 848994

(Firefox :: General, defect)

Description

[PotionClair]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:37.0) Gecko/20100101 Firefox/37.0
Build ID: 20150415140819

Steps to reproduce:

- Use http://www.codecguide.com/windows7_preferred_filter_tweaker.htm to disable the use of Media Foundation for .mp4 . It actually renames the .DLLs to .bak as reported by http://www.reddit.com/r/youtube/comments/34cyca/firefox_is_now_using_the_html5_player_by_default/cqyt635?context=3 .

- Try to play a h.264/AVC video on https://www.youtube.com/ . Generally, HD videos aren't available in VP9 before a few hours, so find a recent HD video on https://www.youtube.com/results?&search_query=hd&search_sort=video_date_uploaded&filters=hd%2Ctoday . Check if you're not being served a VP9 video by right-clicking on the player => Stats for nerds => Mime Type => codecs.



Actual results:

YouTube's html5 video player loads, but shows a never-ending spinning circle.


Expected results:

YouTube should have fallen back to the Flash player.
Maybe it would be a good idea to show once to the user a warning in Firefox that Windows' Media Foundation .DLLs can't be found on the system - for multiple people on that reddit thread ( http://www.reddit.com/r/youtube/comments/34cyca/firefox_is_now_using_the_html5_player_by_default/ ) it was the reason why videos couldn't be played.