Siphalor

And still, the name ATOM hasn’t really caught on.

I feel like everyone just calls it RSS and implicitly refers to ATOM.

Well, it’s actually a bit simpler than that.

You can directly browse a community that technically lives on another instance without ever leaving your instance.

If you’re on the start page of your instance you can e.g. change between seeing Local, Subscribed or posts from all communities (across instances).
You can click around and browse from there without having to leave your instance :)

I recently noticed that this is actually a bug that’s been fixed four days ago (Github).
Until your instance of Lemmy updates, you’ll have to open the post or comment on the original instance using the rainbow button above the comment. GIFs already work on the same site that you post them on.