+ * @brief This signal is emitted when window's auxiliary was changed then display server sent the message.
+ *
+ * Auxiliary message is sent by display server.
+ * When client application added the window's auxiliary hint and if the auxiliary is changed,
+ * display server send the auxiliary message.
+ * Auxiliary message has the key, value and options.
+ *
+ * @param[in] window The window instance
+ * @return The signal to connect to
+ */
+DALI_ADAPTOR_API AuxiliaryMessageSignalType& AuxiliaryMessageSignal(Window window);
+
+/**