Is this a mistake that’s easy to do for an inexperienced instance admin or just a consequence of too much fiddling and shouldn’t be an issue for other instances?

Do we know what could have caused this cache error?

Oh nice. DoH is increasingly important to protect one’s privacy.

Lemmy and Mastodon can talk to each other, not fully but especially Mastodon can see and write to Lemmy communities (although posts are ordered by publishing date since it can’t understand upvotes). What the icon does is show you a comment or post on the original instance it was sent from.

If a Mastodon user sends a comment to Lemmy that icon will link to the same post but as seen on the original instance it was sent from.

That last bar is going to be waaay more vertical once June is over.

Firefox still has some integrity unlike chrome and its clones.