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Turn off youtbe/facebook is now in full screen message

  • 7 replies
  • 1 has this problem
  • 30 views
  • Last reply by cor-el

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Since Tuesday 3rd November 2015 i can no longer tun off that stupid message telling me the obvious, that "Youtube/Facebook is now full screen" Before i could go into "about:config" search for "full-screen-api-approval-required" and set it to false, NOW that option does not show in the string of options, therefore i cannot turn it off anymore. Really Firefox mods it is not that hard to help and support your users and make them browser happy by simply "NOT pointing out the obvious" with this crazy message. Is there anyway to remove this massage when i go full screen on video's now??

Since Tuesday 3rd November 2015 i can no longer tun off that stupid message telling me the obvious, that "Youtube/Facebook is now full screen" Before i could go into "about:config" search for "full-screen-api-approval-required" and set it to false, NOW that option does not show in the string of options, therefore i cannot turn it off anymore. Really Firefox mods it is not that hard to help and support your users and make them browser happy by simply "NOT pointing out the obvious" with this crazy message. Is there anyway to remove this massage when i go full screen on video's now??

All Replies (7)

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I believe that was removed because it's a security concern - something that looks like a simple link could make the webpage go full screen as a phishing attack.

But this add-on appears to remove the notice (I tested it on youtube) https://addons.mozilla.org/en-US/firefox/addon/disable-html5-fullscreen-alert/

Hope that helps, Michael

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I think that the extension relies on a pref that is no longer supported in the current Firefox release.

Try the solution posted here by jscher2000.

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The "Disable HTML5 Fullscreen Alert" does not fix this problem for me. i installed it, restarted Firefox but the message still appears in full screen videos.

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Okay, Stylish users, I posted my rule here for your installation convenience: https://userstyles.org/styles/120517/hide-warning-on-html5-full-screen

Edit: Actually someone else already posted it months ago: https://userstyles.org/styles/116242/hide-firefox-fullscreen-warning

Modified by jscher2000 - Support Volunteer

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Firefox prevents me from downloading this "Stylish addon" and my AV flags up as unsafe. all i want to do is turn off that message :-(

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Oh, sorry, you can install Stylish directly from the Add-ons site which is an approved source of extensions:

https://addons.mozilla.org/firefox/addon/stylish/

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Note that you can also use the code in userChrome.css without the need to use Stylish.

Add code to the userChrome.css file below the default @namespace line.


@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

#full-screen-warning-container{display:none!important}

The customization files userChrome.css (user interface) and userContent.css (websites) are located in the chrome folder in the Firefox profile folder.

You can use this button to go to the current Firefox profile folder:

  • Create the chrome folder (lowercase) in the <xxxxxxxx>.default profile folder if this folder doesn't exist
  • Use a plain text editor like Notepad to create a (new) userChrome.css file in the chrome folder (file name is case sensitive)
  • Paste the code in the userChrome.css file in the editor window
  • Make sure that the userChrome.css file starts with the default @namespace line
  • Make sure that you select "All files" and not "Text files" when you save the file via "Save file as" in the text editor as userChrome.css.
    Otherwise Windows may add a hidden .txt file extension and you end up with a not working userChrome.css.txt file