I'm assuming you are referring to this article.

You don't need a Microsoft account or anything. You will just need to enter the password or PIN that you use to unlock your Windows 10 computer. If you lock your computer with your Microsoft account credentials, then you will be using that, but if you use a regular local account (like a lot of people do), it will just ask for the password that you have locked your computer with.

For example, if you have locked your computer with a local account that has a 5 digit PIN, you need to enter the 5 digit PIN.

Alternatively, you can use a master password in Firefox because Firefox only asks for the Windows PIN if you do not use a master password.

• https://support.mozilla.org/en-US/kb/use-master-password-protect-stored-logins
• https://www.ghacks.net/2020/03/18/firefox-may-soon-ask-for-the-windows-password-to-interact-with-saved-passwords/