How to play 1080p videos on YouTube in Firefox

Martin Brinkmann
Jul 30, 2014

Firefox users who visit Google's video hosting site YouTube may have noticed that the site limits the resolutions that videos are made available in.

In particular, any video resolution higher than 720p may not be made available. Other video resolutions that are available may not be provided as well including 144p, 240p or 480p.

It does not really matter if Adobe's Flash Player is being used to watch videos or if YouTube's HTML5 video player is used: resolutions are limited, usually to 360p and 720p, with all other resolutions are missing from the selection menu.

That's problematic for the user but also for Mozilla, as users may use a different browser to play videos on YouTube in different resolutions.

Google's own browser Chrome and Microsoft's Internet Explorer are for instance not limited in regards to video resolutions.

Fixing the issue

firefox youtube 1080p

What many Firefox users don't know is that it is possible to configure the browser so that all video resolutions are displayed on YouTube when users connect to the site.

Right now, a configuration value needs to be changed for that. In the future, this won't be necessary any longer as Mozilla will enable it by default for all users of the browser.

  1. Load about:config in the browser's address bar and hit enter.
  2. Confirm that you are careful when the prompt is displayed.
  3. Search for media.mediasource.enabled. The preference is set to false by default.
  4. Double-click the preference name to set it to true and enable it.
  5. You may need to restart the browser before the change takes effect.

When you visit YouTube afterwards and click on the cog wheel icon in the interface and there on quality, all available video resolutions are displayed to you on the site so that they can be played.

Note: If you have Adobe Flash installed, you may need to switch to YouTube's HTML5 player. To do so, load and click on the "Request the HMTL5 player" button.

From Firefox 33 on, the button is not displayed anymore so that you cannot switch to Flash manually using the page. The HTML5 video player will be used by default.


Tutorials & Tips

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  1. Pablo said on March 5, 2015 at 11:03 pm

    DASH Playback is a method on how a video should be buffered. If DASH Playback is enabled it will buffer the video in blocks. That means that every time you seek in the video it will have to rebuffer that block and it will not buffer the next block if you’re not at the very end of the current block. If DASH Playback is turned off YouTube will load normally where you can pause the video and it will buffer to the end of the video and you can jump around in the video as much as you like.

    YouTube’s default option has DASH enabled, because it’s buffering faster for people with a good internet connection. YouTube Center also have DASH Playback enabled by default.

    Read more about DASH on Wikipedia

    Please note that by disabling DASH Playback will result in 480p and 1080p not being available. This is because of a recent YouTube change.

  2. Douglas said on February 18, 2015 at 1:02 pm

    Thank you so much,

    This helped me… I couldn’t figure out what the hell was going on.

    I just reinstalled windows 7 today, & I’m thinking maybe that had something to do with it.

    Then, I’m like nope.. this is probably the issue here. Something with mozilla.

  3. anohana said on August 1, 2014 at 7:37 pm

    I got only audio with some videos. :/

  4. TheAslan said on August 1, 2014 at 2:17 am

    Why I have this weird thing on YouTube? This happens only on YouTube.

    Check inside the red box:

    1. Juanma said on December 26, 2014 at 5:56 am

      Try to disable the theme add-on. Use the default skin.

  5. exrelayman said on July 31, 2014 at 6:11 pm

    Use of request html5 caused loss of audio in one attempt and loss of video in another attempt using stable release 31.0.

  6. EuroScept1C said on July 31, 2014 at 9:37 am

    Neither on Fx 32 beta 2 works. I still get up to 720p.

  7. Hugh said on July 31, 2014 at 7:14 am

    Audio disappeared on YouTube videos.

    Enabled mediasource as above.
    Restarted Firefox 31.0
    Got the HTML5 player as described elsewhere on your site.
    again restarted

    Tested on two videos and the audio was missing on both.

    Switched back to default on the same page where we do the get html 5 player and the audio returned.

    Thanks now,


  8. otherguy said on July 31, 2014 at 12:09 am

    FF31 and I get 1080p fine.

  9. Tom said on July 30, 2014 at 6:30 pm

    Similarly, I am using Firefox 31.0 and the problem described in this article does not happen (even though I have media.mediasource.enabled is set to false).

    1. zentaurus21 said on August 1, 2014 at 6:29 am

      same here though the availability of various resolutions is not consistent. the usual resolutions Martin mentions — 360 to 720p — are most often available but there are times when more or all are available. a function of traffic and server activity levels?

      1. Martin Brinkmann said on August 1, 2014 at 7:37 am

        It may also depend on the source video. If it is only 720p for instance, higher resolutions won’t be offered. There are however inconsistencies and it is difficult to determine why that is the case.

    2. Martin Brinkmann said on July 30, 2014 at 6:57 pm

      Are you using the Flash Player?

  10. Q said on July 30, 2014 at 6:13 pm

    I am using Firefox (version 24.7.0), but the problem described in this article does not manifest.

    1. CESAUDIOPRO said on January 10, 2015 at 7:42 pm

      DON’T do this on FIREFOX for the MAC!
      Watch how this locks LONGER HTML5 videos which play just fine in Safari..
      This this one:
      Locks up consistently @ 16 mins.
      With Firefox 35 and earlier version.
      Took me 6 WEEKS to find the problem.
      On 4 Macs!
      NOT reccomended.

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