Clearing Your Complete Web Browsing History in Firefox
An Address Bar that pops up and reports a list of your previously visited websites can clutter your browser and allow others to invade your privacy. Follow these tips to clean up your Address Bar History and keep its contents from prying eyes.
Step 1 Delete single URL address from the Auto Complete feature by typing the beginning of the domain name in the Address Bar. Highlight the address with either an arrow key or your mouse and clicking "Shift" and "Delete" on your keyboard. The address should disappear from Firefox's Auto Complete function.
Step 2 Remove drop-down lists of address bar history by selecting "Tools" from the browser's menu and choosing "Clear Private Data." Make sure that "Browsing History" is checked before pressing "Clear Private Data Now."
Step 3 Disable history to ensure that Address Bar History won't show up again. Go to "Tools" and "Options" in your browser's menu. Locate the "Remember visited pages for the last...days" field and change the number to "0" before clicking "OK" to save your changes. This configuration ensures that your browser won't remember what websites you visit and the addresses won't show on your Address Bar's History on the drop-down menu.
The one-stop solution
1) Type “about:config” (without the quotation marks) into the location bar
2) Click the “I’ll be careful, I promise!” button
3) Filter “browser.urlbar.maxRichResults”
4) Double click the row and reset the value to “0″