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Firefox 43.0b1 cant play videos anymore

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  • 1 has this problem
  • 18 views
  • Last reply by Levan7

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Since updating firefox I noticed that it started to have issues with playing videos.

First I noticed that the videos that I think aren't vp9 stopped playing on youtube. first I started blamed google for this but noticed that videos on NBA.com and ESPN stopped playing as well so it must be something wrong with Firefox.

one more thing I don't have flash installed

So can this issue be fixed ??

Since updating firefox I noticed that it started to have issues with playing videos. First I noticed that the videos that I think aren't vp9 stopped playing on youtube. first I started blamed google for this but noticed that videos on NBA.com and ESPN stopped playing as well so it must be something wrong with Firefox. one more thing I don't have flash installed So can this issue be fixed ??

Modified by Levan7

Chosen solution

The only way I found that fixed this issue was to refresh firefox

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All Replies (7)

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Flash Player (Linux) Version 11.2.202.540 https://www.adobe.com/products/flashplayer/distribution3.html


  • see if there are updates for your graphics drive drivers

https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

See also:

edit: removed stuff not for Linux.

Modified by James

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FredMcD said

Flash Player (Linux) Version 11.2.202.540 https://www.adobe.com/products/flashplayer/distribution3.html
  • see if there are updates for your graphics drive drivers

https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

See also:

edit: removed stuff not for Linux.

Well I don't have flash installed neither I want it on my system, and the firefox would play videos on various websites and now it doesn't

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Seçilmiş Həll

The only way I found that fixed this issue was to refresh firefox

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You can check the prefs.js file in "Old Firefox Data" folder on the desktop (if you kept this folder) to see if there are media prefs listed that might have caused this.

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cor-el said

You can check the prefs.js file in "Old Firefox Data" folder on the desktop (if you kept this folder) to see if there are media prefs listed that might have caused this.

Sadly I deleted them, I was angry and was thinking about switching to chrome. however I had costume preferences that allowed vp9 playback

media.mediasource.ignore_codecs

media.fragmented-mp4.exposed media.fragmented-mp4.ffmpeg.enabled media.fragmented-mp4.gmp.enabled

media.mediasource.webm.enabled media.mediasource.enabled

I had this enabled plus i was forcing hardware acceleration. however this is the first time firefox stopped playing videos and was giving me errors like Video can't be played because the file is corrupt and No video with supported format and MIME type found

I even tried to downgrading firefox sadly no go so I ended up refreshing it however I have not enabled vp9 support or hardware acceleration yet

Modified by Levan7

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If you make such changes to prefs to enabled feature that may not be supported properly then that is at your own risk and you have to remember that you may have to undo these changes in case of problems. In severe cases where you can't start Firefox you need to edit prefs.js or create a user.js file to override defaults.

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cor-el said

If you make such changes to prefs to enabled feature that may not be supported properly then that is at your own risk and you have to remember that you may have to undo these changes in case of problems. In severe cases where you can't start Firefox you need to edit prefs.js or create a user.js file to override defaults.

Well I re enabled all of this after refreshing FF and it works. I don't know what happened there