Because I think bug 665370 should remain WONTFIX.
Set extensions.notAMasterPassword.password
to whatever password you want.
TODO:
- only protect the window if there isn't a master password set
- make it suck less (one of these)
- let the window appear before prompting
- prompt from the prefs window before the password window is open
- prompt on when "show passwords" is clicked
- localize it