How to determine the Facebook ID of a site visitor if the visitor is logged into Facebook?

Question

Facebook

There is my domain, to which visitors come from Facebook ads. Is it possible to determine the Facebook ID or a link to the user's account in order to collect demographic and other data? If yes, how to get a Facebook ID?

Answer 1

The only way to do this is to ask the user to register on your site through a Facebook account. Then (if the user agrees to the terms during registration) you will be able to get the user's data through the API

Answer 2

How do I see a way out of this situation. Chat bots!
They automatically save the user id and can continue to communicate with the client without advertising, but simply by heating the content.