How to prompt user for credentials?

[boston2029]

manage.js has

const user = firebase.auth().currentUser;

// TODO(you): prompt the user to re-provide their sign-in credentials
const credential = promptForCredentials();

user.reauthenticateWithCredential(credential).then(() => {
  // User re-authenticated.
}).catch((error) => {
  // An error ocurred
  // ...
});

But what does it mean by prompt the user to re-provide credentials? Does it mean their email and password or...?