Manipulate browser and OS identification by Firefox?

Question

How can I view and change what browser and OS identity information that are sent by Firefox?

NOTE I've tagged both 10.10 and 11.04 because I want to know how to do so from both of the Ubuntu releases.

Solution 1

In Firefox, open the about:config page and search for useragent. You'll be presented with options to change the different parts that make up a user-agent string:

You can also use an extension like User Agent Switcher, which makes it easy to save a couple and switch between them.

Both of these methods work in Firefox 3.6 (10.10) and 4.0 (11.04).

Solution 2

Another way to view this data is to visit a website like whatsmyuseragent.com from within Firefox (or any other browser).

Comments

[Oxwivi]

Is this useragent thing the same as HTTP referrers?

[Oxwivi]

By the way, edit the add on link to the English page.

[flo]

Oops, thanks. :) No, the referrer is the page you came from, the user-agent is a string that identifies your browser.

[Oxwivi]

Thanks for the clarification. So what can we do about HTTP referrers?

[Oxwivi]

Unlike the screen shot in your answer, only two lines of useragent description appears for me. Even on Windows. But according to a third-party useragent reader, the info includes OS and other info. And is there anyway to keep the entire useragent streak blank/empty?