To address your reason for this question:

> (I'm trying to use Selenium WebDriver and Tor together, but the Tor
> Browser doesn't allow the WebDriver add-on, so therefore, I need to
> use Tor with a regular Firefox browser.)

If you just want to remote-control the Tor Browser, have a look at [Marionette from Mozilla][1]. It is built into the Tor Browser (and every other current Firefox). You **enable it on the command line** by calling

    Browser/firefox -marionette

(inside the bundle). You **initialize** via

    from marionette import Marionette
    client = Marionette('localhost', port=2828);
    client.start_session()

and **load a new page** for example via

    url='http://mozilla.org'
    client.navigate(url);

There is a [tutorial][2] (and further documentation) at readthedocs.

(copy of other [answer][3]).


  [1]: https://developer.mozilla.org/en-US/docs/Mozilla/QA/Marionette
  [2]: http://marionette-client.readthedocs.org/en/latest/basics.html
  [3]: https://tor.stackexchange.com/a/8693/9411