Home page sidebar: What does Guarantor Literature.Cafe mean?

In the sidebar, I see some words highlighted in green saying "Guarantor literature.cafe" and "Endorsements 2"

literature.cafe is another lemmy instance, and "guarantor" seems to be some kind of concept to do with lemmyspace the fediverse chain of trust.

Okay, I think I've found the answer: It's to do with how the fediverse makes sure servers are added using a chain of trust, and to quickly disconnect rogue/spam servers: https://dbzer0.com/blog/overseer-a-fediverse-chain-of-trust/