This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

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

Alissa.Kvashina
Alissa.Kvashina
more options

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?

Chosen solution

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- please refer to the following article on how to reset it: https://support.mozilla.org/en-US/kb/websites-say-firefox-outdated-or-incompatible#w_other-causes

Read this answer in context 👍 3

All Replies (2)

philipp
philipp
  • Moderator
more options

Chosen Solution

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- please refer to the following article on how to reset it: https://support.mozilla.org/en-US/kb/websites-say-firefox-outdated-or-incompatible#w_other-causes

Alissa.Kvashina
Alissa.Kvashina Question owner
more options

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