Credit cards API guestIdentifier value accepts any identifying string

You can now set the guestIdentifier value in the PaymentRequestMetadata object of the credit cards API to any identifying string for a guest. For example, you can set the guestIdentifier value to an email address or phone number. Previously, the guestIdentifier value required a UUID (Universal Unique Identifier) identifier string. You include an identifying string for guests to improve fraud evaluation for credit card payments. For more information about using the guestIdentifier value, see Using guestIdentifier values.