Cookies are rejected, URLs are kept out of the browser history, forms are not auto-filled and pages are not cached. Private browsing, or “porn mode” as it’s often referred to, since that’s one of the more obvious uses, restricts the information that your browser gathers as you visit websites. The following is a detailed excerpt regarding Private Browsing, which I found at. Hey man, I don't know if you'll get this, 'cause it was a while ago that you asked your question, but there's a new version of firefox that is currently in the beta stage that will be released very soon, and it has a feature in the 'Tools' menu that you can activate called 'Private Browsing Session'.

Once you have finished making your selections, click the 'Clear Private Data Now' button and your good to go! You can select 'Cache', 'History', 'Passwords', etc. Once you click this, a dialogue box will open up that gives you a vast range of options. This is the one if you want to click if you want to do it manually, and 'Now'. You will also notice another button that says 'Clear Now'. In there you can select 'Settings', 'Always Clear My Private Data When I Close Firefox', and 'Always Ask Me Before Clearing Private Data' These last two you will have to click the check box and apply your settings in order for it to work. Then click on the 'Privacy' tab and at the bottom it will have a box called 'Private Data'. There it will tell you the exact version of Firefox you have. To check what version you have goto 'Help' and then to the bottom where you will see 'About Mozilla Firefox'. If you have Firefox 3.0.3 I can help you.

Clear my cache firefox