I've just came from a Windows system (in fact, I'm dual booting Ubuntu 12.04 and Win7), and in my Firefox installation back then, when I pressed the middle mouse button (mouse wheel), it displayed a circle that I could move the pointer away from to navigate around the page in a 2-dimensional scrolling. In Ubuntu's Firefox, I don't see this behaviour. Is there a way to enable this feature? I beleive it would require a different version of Firefox, because when I search middle in about:config, ot only has

middlemouse.scrollbarPosition;true

middlemouse.paste;true

middlemouse.openNewWindow;true

middlemouse.contentLoadURL

browser.tabs.opentabfor.middleclick;true

I'm using the canonical release 23.0, by the way.

EDIT: Downloaded a clean install from firefox.com and nothing changed. Maybe it's a system bug?