See previously visited website username with password in Firefox???

 First Step

1)Open Mozilla firefox
2)Click Edit
3)Click Preferences
4)Click Security Tab
5)Click Remember Password for sites
6)close that
7)open www.facebook.com
8)Enter facebook home page with username and password
9)Then Edit->Preferences->Security->Saved passwords->show password for selected one in list

Second Step:
1)Normal Case we all save all our passwords in our system
2)Just Give Master password to protect our secret data