How to open Firefox 3 in Private Mode by Default

Just like Internet Explorer 8 and Google Chrome, the recently released update of Firefox includes a private browsing mode that removes every bit of your browsing history as soon as you close the browser.
In Firefox the private mode can be initiated from the Tools menu or just by pressing the Ctrl + Shift + P shortcut key. But for users who are much concerned with security and privacy while browsing, here is a simple trick that will open Firefox in private mode by default.


Just follow these steps

1. Fire up Firefox and type about:config in the address bar and press Enter.

2. Ignore the warning and press Enter

3. You will be presented with a number of settings with which you can customize different aspects of Firefox, but here we are looking for the private mode settings.
4. In the Filter text box above type in Private. You will see three preferences, but the preference which matter to us is browser.privatebrowsing.autostart.

5. Change its value from false to true by double clicking it. You can also change its value by right clicking and selecting Toggle.

6. Restart Firefox.

7. That’s it, Firefox will now open in Private mode by default, you will see that the Start Private Browsing and Clear Recent History options in the Tools menu are grayed out.