update ACS Chat JS quickstart with real time notifications connection status instruction

Author: glorialimicrosoft

articles/communication-services/quickstarts/chat/includes/chat-js.md

@@ -351,4 +351,20 @@ await chatThreadClient.removeParticipant({ communicationUserId: <PARTICIPANT_ID>
 await listParticipants();
 ```
 Replace **PARTICIPANT_ID** with a User ID used in the previous step (<NEW_PARTICIPANT_USER_ID>).
-Add this code in place of the `<REMOVE PARTICIPANT FROM THREAD>` comment in **client.js**,
+Add this code in place of the `<REMOVE PARTICIPANT FROM THREAD>` comment in **client.js**.
+
+### Subscribe to connection status of real time notifications
+Subscription to events `realTimeNotificationConnected` and `realTimeNotificationDisconnected` allows you to know when the connection to the call server is active.
+
+```JavaScript
+// subscribe to realTimeNotificationConnected event
+chatClient.on('realTimeNotificationConnected', () => {
+  console.log("Real time notification is now connected!");
+  // your code here
+});
+// subscribe to realTimeNotificationDisconnected event
+chatClient.on('realTimeNotificationDisconnected', () => {
+  console.log("Real time notification is now disconnected!");
+  // your code here
+});
+```