I have no idea how to explain this, so I'll just go into how to reproduce this.
1)Create a new profile.
2)Go to a site with a username field. A good one is
Flickr3)type in something to the username and submit it
4)check-- it should now be in Firefox's form-history. Simply clear the username box and start to type it again and it should show a drop-down menu with whatever you typed.
5)download 0.8.1
6)close, restart Fx, go to flickr again and start to type it in again.
Expected results: a single option with whatever you typed
Actual: what you typed and several more lines
This is possibly the most minor bug I think could exist, but it gets annoying.
I could show screenshots, but I won't (unless you need them).