This is just a guess, but I'd imagine that happens because the websites use JavaScript to load the actual content of the page, but Lemmy is just parsing the HTML that is returned.
Also, I really doubt you'd have much luck convincing website authors to completely change their architecture just to get previews to work on Lemmy.
Isn't it the Cloudflare bot detection page that says "Just a moment" (... while we check that you're human)?
It's probably because lemmy servers are constantly loading a bunch of websites to generate previews and Cloudflare decides that those clients look like bots.
Right, I'm hoping that the change might be easy. If it requires major work, then no, it would be very unlikely. Thanks for responding.
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