Yes I like your idea.
Some websites (certainly not all) use this system for security questions.

Many people forget these questions because you never need to use them.

Being able to add them to a log in in especially made fill in boxes would be awesome.
Now I add this kind of information to the notes part of the log in.

A lot of websites require a security question, but you should make it so that users can add the security question to this amazing password manger, which would make it much more helpful for more complex logins.