Somewhere along the line, Mozilla dropped the autofill feature from Firefox. That was when you’d type an address in the address bar (and if you’d been to that particular site before), the rest of the address would pop up. Like this:
Here’s how you can re-enable autofill in Firefox in a few easy steps – one of which requires a little courage.
First, open up Firefox and in the address bar type: about:config and press Enter.
Now, a warning window is going to show up, that looks a lot like this:
Click “I’ll be careful, I promise”. Yes, trust me. We’re only going into the configuration for one specific change and nothing more. Let this be a warning, however, that the area we’re about to go in is not to be entered lightly.
Double-click it, changing the value to true, and restart Firefox.
Should you ever want to change it back, just repeat these steps and change the value to false again.