The chat integration uses a public JavaScript API of the selected chat provider. You have to install the chat widget into your application as you would normally do without Product Fruits integration in place. Then follow this article.
Turning on the chat integration
Go to Widgets -> Life Ring Button
Switch to the Tools Buttons tab.
Enable the Show Chat button checkbox and select your chat provider. We support ZenDesk Web widget and Live Chat (Zopim). Select the one you use in your application.
Hide ZenDesk launcher button
Please note that you should check the ZenDesk official documentation to get accurate information on their API.
Follow ZenDesk documentation on how to integrate the ZenDesk widget into your application
Hide the ZenDesk default launcher button by selecting 'custom launcher' on the styling page of the messaging settings.