I've checked our server logs and it seems to have been an issue with a timeout.
This might be something that is fixed once we update to a newer Lemmy version that performs metadata processing in the background instead of while receiving the post.
That's odd. It seems like your post didn't federate from feddit.org to lemmy.world for some reason. There does not appear to be significant federation lag between the two instances at the moment.
It's visible now. I pasted the feddit.org URL into the search bar on lemmy.world, which forces lemmy.world to fetch the post.