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Videos / mp4s will not play in Firefox on Mac

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  • 2 have this problem
  • 18 views
  • Last reply by cor-el

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I have mp4 video content served up by CDN that will not stream in my Firefox browser (35.0.1) on Mac OSx (10.10.1). It downloads the file and opens the file in QuickTime (the same is true in Chrome). It will stream perfectly in Safari. In preferences, I see QuickTime Plug-in 7.7.3 associated with mp4 content, but my QuickTime Player is 10.4. If I change the default to my QuickTime Player it does not change the behavior.

I have mp4 video content served up by CDN that will not stream in my Firefox browser (35.0.1) on Mac OSx (10.10.1). It downloads the file and opens the file in QuickTime (the same is true in Chrome). It will stream perfectly in Safari. In preferences, I see QuickTime Plug-in 7.7.3 associated with mp4 content, but my QuickTime Player is 10.4. If I change the default to my QuickTime Player it does not change the behavior.

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With what content type does the server send the files?

See also your previous thread about issues regarding server configuration.

You can check content types supported by a plugin on the about:plugins page.

I don't know what the current state for mp4 support in Firefox is for playing with the HTML5 media player.

  • bug 1043696 - Enable Apple PlatformDecoderModule for HTML5 video playback (MP4 playback on OSX)

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https://bugzilla.mozilla.org/page.cgi?id=etiquette.html