TenFourFox and YouTube

Michael McMurtrey's Avatar

Michael McMurtrey

31 Jan, 2016 01:00 AM

I've been using TenFourFox on my PowerMac G4 for some time now and have been very happy with it. However, today I started seeing this notice every time I open a YouTube page:

"You're using an older version of Internet Explorer that we'll soon stop supporting. Please update your browser to the latest version."

Why dies YouTube think I'm using Internet Explorer? Does this mean that at some point I will no longer be able to view YouTube videos using TenFourFox?

  1. Support Staff 1 Posted by Chris (chtrusch... on 31 Jan, 2016 06:41 AM

    Chris (chtrusch)'s Avatar

    Hello, sounds like your're sending the wrong useragent string to Youtube. Go to http://whatsmyuseragent.com/. If it says something about "MSIE" instead of Tenfourfox/Firefox, you can reset the useragent in about:config. Right-click general.useragent.override and choose reset.

  2. 2 Posted by Michael McMurtr... on 31 Jan, 2016 02:18 PM

    Michael McMurtrey's Avatar

    According to whatsmyuseragent.com, my user agent string is:

    Mozilla/5.0 (Macintosh; PPC Mac OS X 10.5; rv:38.0) Gecko/20100101
    Firefox/38.0 TenFourFox/7450

    About:config says:

    general.useragent.locale: en-US

    general.useragent.site_specific_overrides: true

    But as of this morning, YouTube still thinks my browser is IE.

    Michael McMurtrey
    Carrollton, TX

  3. Support Staff 3 Posted by Chris (chtrusch... on 31 Jan, 2016 02:37 PM

    Chris (chtrusch)'s Avatar

    Then I'm out of ideas, I'm sorry. I can't reproduce the behavior you described when the browser sends our default useragent string. Or maybe you have some site specific override for Youtube defined (by an addon)? This should then show up in about:config as well. general.useragent.site_specific_overrides = true is default and does not cause this behavior for me.

  4. 4 Posted by cym224 on 27 Jun, 2016 08:10 PM

    cym224's Avatar


    I was having the same problem and today, Youtube refused to let me watch anything. My problem was due to the add-on "ALL HTML5" that was altering the useragent string. Disabling this solved the problem.

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