This will undoubtedly be a front-end to the existing iCloud Keychain password store. Details of how this works are explained in "Apple Platform Security": http

This will undoubtedly be a front-end to the existing iCloud Keychain password store. Details of how this works are explained in "Apple Platform Security": https://help.apple.com/pdf/security/en_US/apple-platform-security-guide.pdf https://help.apple.com/pdf/security/en_US/apple-platform-sec...