You may come across one you just might like. They change on a regular basis.
Edit for rule #2 - Trending communities show you new/active communities in the instance you are browsing from the instance’s home page. Example: My account lives on lemmy.world, but if I visit lemm.ee I will be able to see that instance’s newest and/or most active communities. Just another way to explore Lemmy and the fediverse from another noobie user learning things as I go along. :) Cheers!
Can you post a screenshot? I’m using the web (desktop) version and there’s no such thing whatsoever.
Edit: found it! It’s already open in the top right-hand side of the page on the instance home page.