One of the long-standing issues we have in/on the fediverse is that when I have a link in my post that goes to another post on my instance, people on other instances will click that link and be taken to MY instance, where they can't comment, don't have an account, aren't logged in, etc and they will try to log in using their login credentials for their home instance then wonder why it doesn't work.

When someone links to https://lemmy.world/post/39832275 and I'm on piefed.social I want to see https://piefed.social/... not the copy on lemmy.world!

As of PieFed v1.4, links like that will automatically be converted to link to the local copy of the post, where 'local' is whatever is local for the reader. See the linked video where I demonstrate this in action.