Front End

Let's see how FacebookMessage looks like in the OpenCart storefront.

This is the default view of the Messenger chat bubble in your store:

facebook-message

Your customers can now start a conversation with you without leaving your OpenCart website.

All you need to do is respond from your Facebook business page's messages.

facebook-message-information

Customers will the following controls over their chat with you.

To summarize, you have the Messenger app itself working like it normally does, but within your OpenCart store.