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Youtube video won't play 720p in Firefox. 1080p works fine but choosing 720p will not change resolution from 360p. IE and Chrome do not have this issue.

  • 2 回覆
  • 10 有這個問題
  • 25 次檢視
  • 最近回覆由 hasturlord

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Youtube video won't play 720p in Firefox. 1080p works fine but choosing 720p will not change resolution from 360p. it is not just the video but the player will stay in 360p when going fullscreen. IE and Chrome do not have this issue. Flash is updated as if Firefox. I tried deleting history and cookies as well. I right click on the videos and they say Adobe Flash so i assume they are not in HTML5 but i am not sure. It happens for all videos that have an option for 720p but not 1080p. If they have a 1080p option then 720p works as well. if i try Chrome or IE then the videos will play in 720p.

Youtube video won't play 720p in Firefox. 1080p works fine but choosing 720p will not change resolution from 360p. it is not just the video but the player will stay in 360p when going fullscreen. IE and Chrome do not have this issue. Flash is updated as if Firefox. I tried deleting history and cookies as well. I right click on the videos and they say Adobe Flash so i assume they are not in HTML5 but i am not sure. It happens for all videos that have an option for 720p but not 1080p. If they have a 1080p option then 720p works as well. if i try Chrome or IE then the videos will play in 720p.

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 right click on the videos and they say Adobe Flash so i assume they are not in HTML5 but i am not sure. 

What does it say when you go to https://www.youtube.com/html5?
Mine says The default player is currently used. which of course means I'm using Flash and not the HTML5 player.

Can you try to start Firefox in Safe Mode to see if Firefox works properly with no error? You can start Firefox in Safe Mode below:

  • Windows/Mac: Go to Help > Restart with add-ons disabled
  • Linux: Run firefox -safe-mode in the Terminal/Konsole

If Firefox opens up fine with no problems, it's probably one of your extensions that's causing the issue. You can re-enable your add-ons one by one until you find the one that causes the issue upon being re-enabled.

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The link gave the same result as it did for you with using the default player.

I rebooted into Safe Mode and had the same experience with the Youtube videos. It allows me to choose 720p as the resolution but it does not load 720p but keeps at 360p default. The player interface stays at 360p as well.

I did try to rewind the video back to the start to let it buffer from the beginning to try to see if it would load 720 after I made the choice for it (sometimes i just get a spinning gear until the stream catches up to where it was buffered in the original resolution) but it did not change.

This is only in Firefox and only started happening a few months ago.