What's the simplest way to add a Chat widget to a HTML website?

[gianpaj]

Hi,

I managed to deploy the Firebase functions (https://github.com/chat21/chat21-cloud-functions)
and I would like to add a chat to a basic HTML website.

Is there a demo where I can do that? Or the only way is via an angular website (https://github.com/chat21/chat21-web-widget)?
or build it into a single .js file to be able to add it, like an Intercom or Drift chat?

Thanks a lot