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Can't play embedded mp4 videos in Firefox on Linux

  • 5 replies
  • 1 has this problem
  • 19 views
  • Last reply by anini

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I installed Ubuntu Mate 16.04 (32-bit) next to Win 7 (dual boot), and it has Firefox 59.0 already installed. When I try to play videos (mp4), on some sites it won't play. In Windows + Chrome it works. While trying to find solution, I found helpful site https://www.quirksmode.org/html5/tests/video.html , which shows me that what I'm missing is H.264/MP4 on FF 4.0b11. YouTube works. Is there a way to play this kind of video in Firefox?

I installed Ubuntu Mate 16.04 (32-bit) next to Win 7 (dual boot), and it has Firefox 59.0 already installed. When I try to play videos (mp4), on some sites it won't play. In Windows + Chrome it works. While trying to find solution, I found helpful site https://www.quirksmode.org/html5/tests/video.html , which shows me that what I'm missing is H.264/MP4 on FF 4.0b11. YouTube works. Is there a way to play this kind of video in Firefox?

All Replies (5)

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One package(s) that may not get installed during a Linux install is related to FFmpeg. Look for it in the package manager.

If Firefox is still running when you install this package then you may need to restart it. You can then check at https://www.youtube.com/html5 as all checks should then be blue.

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Thank you so much on quick answer. I installed FFmpeg through package manager, opened link you provided and all checks were blue (though, I remember that yesterday I did the same check and all the checks on youtube were blue also). YouTube is working, I never had problem with it, but problem with some sites remains. I have the same problem with Firefox on Win8.1 and Ubuntu Mate, on different hardware. I checked various suggestions for settings in about:config in Firefox, and all that I did so far is not making any changes - videos on the site (http://moviesonline.la) are still not working in Firefox, while they are working in Chrome..

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Hi, I have no problem with the site, no added codecs, just straight Firefox. Some interesting uninstall info if not use/read it as want to get the cleanest you can get when uninstalling. Do not know where you get your compile from but there is one on Mozilla page https://www.mozilla.org/firefox/all/

So as clean as can get, nice new compile, do not use old profile but test 1st. See what happens. If still bad then try a earlier version in the 57+ range after cleanup again, which you know you can update from. https://ftp.mozilla.org/pub/firefox/releases/

Please let us know if this solved your issue or if need further assistance

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Are you using any adblockers or a VPN for this site ?

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Unfortunately I didn't resolve the problem. I tried different Firefox (earlier versions as you recommended), different hardware and different OS (Win8.1 64bit, Linux mint 32bit, Linux ubuntu mate 32bit), but the problem remained. Yet, on the same network my husband doesn't have that problem on his laptop. We tried to find differences, but didn't find at the end... I didn't use any adblock or vpn on linuxes.

Thanks everyone who offered help. I give up on it at this moment, as I have no idea what else to try.