I'm building a tool that works with contact cards (iCloud CardDAV as source). I need to obtain the pronouns set for a user to know if they are to be addressed as a he, she, etc.
Pronouns set on a contact in Apple Contacts sync to iCloud and appear on the CardDAV vCard as itemN.X-ADDRESSING-GRAMMAR, but the value is opaque after base64 decode (not plaintext, XML plist, or binary plist). Third-party CardDAV clients authenticated as the account owner therefore cannot read pronouns, even though other contact fields (name, phones, emails, related names, etc.) are readable.
RFC 9554 PRONOUNS is not present on these cards.
How do I get these from contact cards?