Is the Facebook crawler blocked on the server level?

[Admin (Owner of PFH)]

Link preview on certain social media platforms might not be working because of the security measure taken to reduce abuse to our system:

What does trailing ?i=1 at the end of my URL mean?

When you register a new account and go to the website URL, you may see a trailing parameter, such as: ?i=1. What does it Do? This parameter is actually a security measure to ensure that your website is accessible only through regular web browsers. When your URL is first accessed, it is redirected to ?i=1 which means that it is the first attempt the validate the browser in which case a cookie is setup to check if challenge is passed. When it is showing ?i=2, this means that the security system …