No matter what options I change (I tried everything under about:config, I even completely reinstalled firefox), html5 videos don't play (format not supported, wrong mime … (read more)
No matter what options I change (I tried everything under about:config, I even completely reinstalled firefox), html5 videos don't play (format not supported, wrong mime type etc.). On youtube however, the html5 player works fine.
Examples of videos not working:
My Win7 can play everything - I do not use Windows Media Player and normally keep those features deactivated but actually tried activating all Windows Media features (I normally use the K-Lite codec pack and in my desperation also tried CCCP). It did not help.
Downloading the videos lets me play them without problems.
All my media.* preferences in about:config have the default value, and I tried changing stuff - the most that achieves is just disabling html5 videos entirely - which is not a solution.
I also deactivated all addons/plugins, I restored Firefox, uninstalled and reinstalled it, even tried the 64bit developer version.
https://html5test.com/ tells me that my firefox supports everything but DRM and MPEG-4 ASP under video.
http://detectmybrowser.com/ tells me I can play ogg but not h264 or webm.
https://www.youtube.com/html5 tells me my firefox supports everything youtube needs (if I flip media.mediasource.webm.enabled, of course).
Again, on youtube everything works (right-clicking the videos gives me the "About the HTML5 player" option), everywhere else (as far as I have seen) I get the "format not supported/wrong mime type error.
Firefox 37.0.2 on Windows 7, I started noticing the problem with the 37 update - I guess because firefox switched to html5 instead of flash as default? I've been using html5 on youtube since it became possible.
Also, my plugin-container crashes whenever I close firefox, I have tried clearing cookies/history/cache (besides resoting/reinstalling, which should include this) since that was a suggested solution. The problem always comes back, no matter what sites were loaded. If I exit firefox only seconds after opening it the plugin-container might not crash. No idea if this is related to the html5 issue.
So, any ideas I can try to make html5 videos work?