I’m very new here but I decided to check and compare the posts in a community on lemmy.world (where I have my account) and that same community on the instance where it resides and the posts were almost all completely different! Is that how it’s supposed to work or are they supposed to be synced? Sorry if this is a noob question, I’m new here
Ideally yes, posts should be mirrored exactly across all instances.
In practicality, lemmy.world and others are having some outgoing federation issues. Hopefully wrinkles will get ironed out with time but I would expect the issues to get worse over the next few days as the API apocalypse happens.