so you can tell where something is coming from by checking the full @/name. you can see this in the sidebar for magazines, or hovering over someone's name to see for the users. there's userscripts to show it automatically and I think it's planned to have an official option to do so.

What makes federated threads show up here on kbin?

By default, we can access every other federated instance. However, it might not show up if someone isn't subscribed to the person or magazine. Threads for magazines should be 100% in sync across instances (though sometimes things are a bit finnicky due to the influx of users).

Are there any that don't?

Content from other instances won't show up here if:

1. it's not part of what the collective kbinauts have subscribed to (if we subscribe to another instance's magazine, it pulls in that content for everyone here.)

2. if another instance decides to block or "defederate" with us. as of now I think every instance is federating with kbin.social so this shouldn't be an issue.

3. if you mark that you don't wish to see federated content. this will only show you stuff from kbin.social.