I just wondered if I could bring it up before entering a password.
Typically, at least the behavior I've experienced, the prompt is generally produced at the time the password is enter and not beforehand.
I suppose if you reset the browser to factory settings it would resume it's previous behavior of prompting you for a save.
The only other thing I have noticed is this registry key
Computer\HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\IntelliForms
In the right pane for mine, which seems to behaving normally the "AskUser" value is set to zero