Whitelist Domain to render Facebook Customer Chat Plugin

For Security reasons Facebook, customer chat plugin renders only on the Websites that are whitelisted within the relevant Facebook page.

Whitelist Domain Name

From your Facebook page

Click on ‘Settings’

Click on ‘Messenger Platform’ tab

Scroll down the page – you can notice ‘Whitelisted Domains’ options

Add full qualified domain name,

For E.g  –   https://example.com/

Website must server from ‘https’ protocol.

whitelisted domains

Add the domain name that serves over HTTPS,

If SSL Certificate is not installed add domain name without HTTPS also, this may work.

Add Fully Qualified domain name. Adding Localhost, IP address may not support.

Add the domain name, how your website is loading. 
To Avoid Confusion
Its better to add with http and https versions –  http://yourdomain.com, https://yourdomain.com.

Adding domain with “www” is like adding a subdomain, if you are accessing your website without “www”, add a domain name without “www”

Adding domain name in multiple ways won’t cause an issue like http://example.com,  https://example.com,  https://www.example.com