While the Tor browser is based on Firefox ESR, it is modified with additional privacy and security settings to protect users of the browser while using the program. Considering that Tor browser is used by some in critical situations, whistleblowing, publishing news or communication, it is only natural that a stronger focus on privacy and security is necessary.
Mozilla acknowledges these modifications, and plans to integrate some of them in Firefox natively. In fact, the company has already begun to integrate some in Firefox, and plans to integrate others in the future.
Tor-specific privacy settings are often not suitable for Firefox's mainstream audience. That's why you need to enable these settings manually in Firefox before they become available.
(Score: 3, Informative) by janrinok on Wednesday July 06 2016, @06:06PM
I assume that you have maintained the accepted practice of not reading TFA....?
The settings do not remove any functionality but give you the option of ensuring that your browser does not respond to a few queries that might permit it to be differentiated from others using the same browser. This is claimed to be to prevent some types of browser fingerprinting. How useful this will actually be - they will have your IP if you are not actually using TOR - remains to be seen. And they can hardly be accused (in this particular instance) of removing functionality - if you don't select the options then Firefox will respond to queries just as it does today.
And, as you point out, you can still choose to use any other browser should you wish to do so.
I am not interested in knowing who people are or where they live. My interest starts and stops at our servers.