PropertiesChanged signal is missing in Client::DBus::PropertiesInterface

[Kaffeine]

The modern approach to use the org.freedesktop.DBus.Properties.PropertiesChanged signal for property changed notification is not supported on the client side.

• Channel.Interface.RoomConfig1
• Channel.Interface.Subject2
• Channel.Interface.CaptchaAuthentication1

See also: TelepathyIM/telepathy-glib@5894586