Here is a quick tip that is not that well known. If you want to start private browsing in a hurry, and you don’t have time to dive through the menus to start it (Tools > Start Private Browsing) then just type about:privatebrowsing into your address bar.
There you have it. Once you have done so, it will ask you if you want to switch into Firefox’s private browsing mode. You could also save about:privatebrowsing as a bookmark, so you have easy one click access to the private browsing mode, without adding any extra add-ons to Firefox.
Now here is my challenge to all of you out there, does anybody know a quick way to stop private browsing, and return your browser back to normal (other than the traditional menu method). If you do, leave it in the comments!