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The fullscreen option on YouTube.com no longer works in Mozilla. Why is that?

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  • 65 have this problem
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  • Last reply by guigs

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I noticed a few days ago that the fullscreen function no longer works for embedded YouTube videos in Mozilla. Then tonight it occurred too me to check and see if t works when you watch a video at YouTube.com. I tried several videos at random and none of them had the fullscreen function. The fullscreen button (box) is there, but when I click on it nothing happens.

I also tested videos at Hulu.com, DailyMotion.com, the Internet Archive and Veoh.com, and the fullscreen function is fine on all of those sites - it is only YouTube that seems to have a problem. I also tested the same videos in the Internet Explorer browser and they work there for all of the sites mentioned, including YouTube.com.

I hope this can be repaired, I really like the Mozilla browser and would hate to have to switch to something else.

I noticed a few days ago that the fullscreen function no longer works for embedded YouTube videos in Mozilla. Then tonight it occurred too me to check and see if t works when you watch a video at YouTube.com. I tried several videos at random and none of them had the fullscreen function. The fullscreen button (box) is there, but when I click on it nothing happens. I also tested videos at Hulu.com, DailyMotion.com, the Internet Archive and Veoh.com, and the fullscreen function is fine on all of those sites - it is only YouTube that seems to have a problem. I also tested the same videos in the Internet Explorer browser and they work there for all of the sites mentioned, including YouTube.com. I hope this can be repaired, I really like the Mozilla browser and would hate to have to switch to something else.

Chosen solution

Please update to the most recent version of Firefox:

Hi Jumpcity, I understand that both embedded youtube videos and youtube.com videos do not have the function to view in fullscreen mode or nothing happens. First check if you are using the Flash Player or the HTML5 player. (Just check if there is a puzzle piece in the url bar of the browser, this will mean that the flash player is being used)

Second check the page permissions to make sure that there is not a stored feature preventing it from going into fullscreen mode.

  1. Right click on youtube.com
  2. Select "Page Info"
  3. Click on the "Permissions" Tab of the window the opens up and scroll down until you see "Fullscreen" and make sure it is set to "Allow" or "Default"

Else try this: [ http://mzl.la/1C40yVx Flash videos won't play full screen]

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Chosen Solution

Please update to the most recent version of Firefox:

Hi Jumpcity, I understand that both embedded youtube videos and youtube.com videos do not have the function to view in fullscreen mode or nothing happens. First check if you are using the Flash Player or the HTML5 player. (Just check if there is a puzzle piece in the url bar of the browser, this will mean that the flash player is being used)

Second check the page permissions to make sure that there is not a stored feature preventing it from going into fullscreen mode.

  1. Right click on youtube.com
  2. Select "Page Info"
  3. Click on the "Permissions" Tab of the window the opens up and scroll down until you see "Fullscreen" and make sure it is set to "Allow" or "Default"

Else try this: [ http://mzl.la/1C40yVx Flash videos won't play full screen]