Firebase View

First go to Firebase console Create a Project if you don't have any project.

Set the name for the project and Continue

Make sure that enabled the Google Analytics for this project and click the Continue and Create the project

Then you need to create web app in that project for that click the web app icon in the project like shown below

Set the name for the app and register the app

Here you can see all the details we need you can copy them and after that select npm and click the Next Button

After that you can click Next Button for Install Firebase CLI

After that click the Continue to console

After that you can see the app inside the project and click on the setting icon of the app to see the details of that app

You can see the credentials(not server key and vapid) we need in odoo in the General --> Your apps

You can create the server key we need in odoo.For that goto the Cloud Messaging --> Cloud Messaging API (Legacy) --> 3 dots -->Manage API in Google Cloud Console --> Enable the Cloud Messaging

After that you can see the Server key in Cloud Messaging API (Legacy)

Now we need to create a Vapid goto the Cloud Messaging --> Web configuration --> Generate Key pair

After that you can see the public key of the Vap id Cloud Messaging --> Web configuration

Configuration Settings

Goto the Settings and enable the 'Enable Push Notification' then you can set the credential

Its very important that You must Allow the notification in the web browser

After Allowing the notification access in the browser you can click the "TEST CONNECTION" Button

Then you can see a notification on the system, and you can see a green popup

Notification View

After that you can send message from the chatbox module or in the discuss module

Notification View

Then you can see a popup notification in the other user and when you click on that it will be redirected to the odoo instance