Update FAQ.md

FAQ.md

@@ -2,16 +2,26 @@
 
 ## iCloud Authentication
 
-If your Apple account has two-factor authentication enabled,
+### MFA
+
+If your Apple account has two-factor authentication (multi-factor authentication, MFA) enabled,
 you will be prompted for a code when you run the script. Two-factor authentication will expire after an interval set by Apple,
-at which point you will have to re-authenticate. This interval is currently two months.
+at which point you will have to re-authenticate. This interval is currently two months. Apple requires MFA for all new accounts.
 
 You can receive an email notification when two-factor authentication expires by passing the
 `--smtp-username` and `--smtp-password` options. Emails will be sent to `--smtp-username` by default,
 or you can send to a different email address with `--notification-email`.
 
 If you want to send notification emails using your Gmail account, and you have enabled two-factor authentication, you will need to generate an App Password at <https://myaccount.google.com/apppasswords>
 
+### FIDO
+
+Authentication to iCloud with hardware keys (FIDO) is not supported.
+
+### ADP
+
+Advanced Data Protection (ADP) for iCloud accounts is not supported because iCloudPD simulates web access, which is disabled with ADP.
+
 ### System Keyring
 
 You can store your password in the system keyring using the `icloud` command-line tool:
@@ -44,14 +54,9 @@ This error often happens because your account hasn't used the iCloud API before,
 
 If you are still seeing this message after 30 minutes, then please [open an issue on GitHub](https://github.com/icloud-photos-downloader/icloud_photos_downloader/issues/new) and post the script output.
 
-
 ## Access from Mainland China
 
-Access to iCloud.com is blocked from mainland China. `icloudpd` does not currently support icloud.com.cn version yet.
-
-## iOS 16 Shared Library
-
-iOS 16 feature to share libraries between accounts is [not supported](https://github.com/icloud-photos-downloader/icloud_photos_downloader/issues/455) yet.
+Access to iCloud.com is blocked from mainland China. `icloudpd` can be used with `--domain cn` parameter to support downloading iCloud phtotos from mainland China, however, people reported mixed results with that parameter.
 
 ## MacOS binary