I see that WhatsApp does have the option of setting up extra security for ones account. It appears it is a 6 digit ("static") passcode (PIN). WhatsApp will periodically ask for this same passcode when you launch the app (this helps you remember your code).
Because it isn't a login as such but rather one "simply" enters a 6 digit PIN when periodically prompted I wasn't sure how to best store such easily forgotten information in 1P. Is this where one would use...."Notes?