Do you mean a reminder to update this PP or a reminder to enter the PP so you won't forget it ?

Each time you open the about:logins page in a session for the first time then you get the PP prompt. This also happens if Firefox needs access to the logins like when you visit a website for which you have a login stored or are using Sync as Firefox also stores the credentials to connect to Sync in the Password Manager.

Ah, thank you for your prompt interest. No, I mean that I don't like writing passwords down and I sometimes forget them, even if only temporarily. So, when I am prompted to enter the PP it would be good for me if I could ask for a password hint I had set up that would only mean something to me. I hope that this clarifies. It's particularly important for the PP because there is no way to reset it without losing the saved passwords. Thanks again.

No, Firefox doesn't have the feature to give a hint to bypass the PP as knowing the answer to this hint won't help. The PP is used to encrypt the actual encryption key stored in key4.db with an extra level and only the exact encryption key can be used to access the logins.

Thank you. Maybe the attached will make it clearer. I had written more but navigated away and the text I had written was wiped. The hint is not a bypass of the PP, but a reminder. It is (or could be) "Troilus and Cressida" which invokes a personal memory which reminds me of the PP I created.

Thank you again.

That looks more like site login issue then a Browser problem. If you can't write the logins down then you need to do some homework and find a 3rd party software to store and encrypt your logins from unauthorized users.