Firefox shows you the previous addresses you have been to as soon as you start typing in the address bar. While this auto-complete feature is a tremendous time-saver, there may be instances when you want to keep certain URLs…ummm, private. Of course, you can delete your browsing history, but that would remove all the URLs you have visited and disturb your productivity.
Deleting a single URL from the dropdown list is actually a matter of pressing the Delete key only.
Here’s the simple (but very useful) how-to:
On the address bar, as soon as you start typing an address, the dropdown appears with the URLs of pages you’ve visited (and any matching ones in your bookmarks) with the letters you were typing in them.
Simply use the arrow key to scroll to the address you want to delete, and then press the Delete key to remove the specific URL you would rather keep private. Yes, that is all you need to do. Try it out.