It shows that the website it down. Then, when I click to open the link in a browser, it shows “Do you want to download learn.trainingauthors.com”? If I click the X on that popup, the site will finally open.
The first error I fear is a problem with the Facebook app, which is unrelated from the actual website. The second one might be something to with the additional query string Facebook adds to each URL. I am wondering if it’s due to something on the server when seeing that query string, as I can’t see how Cloudflare can cause this kind of issue.