The user's custom claims object if available, typically used to define
user roles and propagated to an authenticated user's ID token.
This is set via _BaseAuth.setCustomUserClaims.
The user's hashed password (base64-encoded), only if Firebase Auth hashing
algorithm (SCRYPT) is used. If a different hashing algorithm had been used
when uploading this user, as is typical when migrating from another Auth
system, this will be an empty string. If no password is set, this is
null. This is only available when the user is obtained from
_BaseAuth.listUsers.
The user's password salt (base64-encoded), only if Firebase Auth hashing
algorithm (SCRYPT) is used. If a different hashing algorithm had been used to
upload this user, typical when migrating from another Auth system, this will
be an empty string. If no password is set, this is null. This is only
available when the user is obtained from _BaseAuth.listUsers.
The date the user's tokens are valid after, formatted as a UTC string.
This is updated every time the user's refresh token are revoked either
from the _BaseAuth.revokeRefreshTokens.
API or from the Firebase Auth backend on big account changes (password
resets, password or email updates, etc).