content Serializer
fun Set<SerializerMapping<out EventContent>>.contentSerializer(content: EventContent): Pair<String, KSerializer<out EventContent>>
fun Set<SerializerMapping<out EphemeralEventContent>>.contentSerializer(content: EphemeralEventContent): Pair<String, KSerializer<out EphemeralEventContent>>
fun Set<SerializerMapping<out GlobalAccountDataEventContent>>.contentSerializer(content: GlobalAccountDataEventContent): Pair<String, KSerializer<out GlobalAccountDataEventContent>>
fun Set<SerializerMapping<out RoomAccountDataEventContent>>.contentSerializer(content: RoomAccountDataEventContent): Pair<String, KSerializer<out RoomAccountDataEventContent>>
fun Set<SerializerMapping<out RoomEventContent>>.contentSerializer(content: RoomEventContent): Pair<String, KSerializer<out RoomEventContent>>
fun Set<SerializerMapping<out StateEventContent>>.contentSerializer(content: StateEventContent): KSerializer<out StateEventContent>
fun Set<SerializerMapping<out MessageEventContent>>.contentSerializer(content: MessageEventContent): KSerializer<out MessageEventContent>
fun Set<SerializerMapping<out ToDeviceEventContent>>.contentSerializer(content: ToDeviceEventContent): Pair<String, KSerializer<out ToDeviceEventContent>>