Crappy Design

Interesting, thanks. I can see the video if I view via voyager here: https://m.lemmy.world/search/lemmy.world/c/[email protected]

That it displays in some views but not others though, reinforces (to me) that the problem is with the app, not the post. I'd gently suggest (to the person I originally replied to) that if something isn't displaying, the first thing to do is see what it looks like in a browser, and if that's okay, report the problem to the app author, not reply to the OP. We should all just be able to post stuff, without worrying about every feasible way that someone might want to view it.