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Why do I see "Your browser is not supported" on many sites with firefox 15?

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Some sites, like trello.com and many others tell that I seem to use old browser, or that my browser is not supported, and ask me to download Firefox 4 or older. Is it just irresponsible web-developers, who put this sign for any browser except those in a list, and who then forget to update the list? Or is it some issue with FF itself? Is there any simple workaround without using UserAgent changing plugins?

Some sites, like trello.com and many others tell that I seem to use old browser, or that my browser is not supported, and ask me to download Firefox 4 or older. Is it just irresponsible web-developers, who put this sign for any browser except those in a list, and who then forget to update the list? Or is it some issue with FF itself? Is there any simple workaround without using UserAgent changing plugins?

Asịsa ahọpụtara

hello Chertik89, maybe the firefox useragent (the information the browser sends to websites to identify itself) got overwritten or corrupted - please refer to the following article on how to reset it: https://support.mozilla.org/en-US/kb/websites-say-firefox-outdated-or-incompatible#w_other-causes

Gụọ azịza a na nghọta 👍 3

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Asịsa Ahọpụtara

hello Chertik89, maybe the firefox useragent (the information the browser sends to websites to identify itself) got overwritten or corrupted - please refer to the following article on how to reset it: https://support.mozilla.org/en-US/kb/websites-say-firefox-outdated-or-incompatible#w_other-causes

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Many thanks, it helped, my useragent appeared to be overwritten by apple updater.