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Firefox embeds too much information in the browser's User-Agent header field (even the build date, which I find unnecessary).


Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20091109 Firefox/3.5

Mozilla/5.0 (X11; U; Linux i686; en-US; rv: Gecko/20100722 Firefox/3.6.8

As a result, User-Agent one uses tends to be unique on a not-so-popular websites, which I would like to avoid to retain certain anonymity on the web.

So, what would be the most common Firefox User-Agent?

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migrated from Aug 5 '10 at 0:32

This question came from our site for professional and enthusiast programmers.

closed as too localized by random Dec 8 '11 at 1:29

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

Is that really a question for SO? Retaining anonymity by forging the User-Agent string doesn't sound programming related. – Alexandre Jasmin Aug 5 '10 at 0:19
Some websites only allow HTTP access to a limited set of User-Agents. The odds are the most common ones are allowed to do so. So yes, it is in a way programming-related. – Anonymous Aug 5 '10 at 0:25
The site operator has your IP address which tells a lot more about you than a UA string. If you are looking for anonymity via this route, you've already lost. – msw Aug 5 '10 at 0:37
Most browser fingerprints (including UA, installed fonts, plugins, time, etc) are unique and easily tracked, even without an IP address. There is no escaping big brother anymore, as demonstrated on this site: – user108629 Dec 8 '11 at 0:33

Use the latest stable build of Firefox, and all they can see is that you're using the latest stable build of Firefox.

Mine is:

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20100722 Firefox/3.6.8

Apart from saying I'm on Windows XP and speak English, all it says is that I'm on Firefox 3.6.8 (based on Gecko as of 20100722, which will be common to all people on this version).

At any given time, I'd say the most common Firefox user-agents will be either the latest or the previous stable version (depending on how long it's been since released), running on Windows XP, English(US).

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"I'd say the most common Firefox user-agents will be either the latest or the previous stable version" Is this really the case? It would be nice if someone is able to provide a histogram of firefox user-agents to prove/disprove that it is the case. – Anonymous Aug 5 '10 at 0:29