Hello,

when someone connects to my server it is displayed twice on luckperms editor.

When I was the first to be connected to my server I was displayed normally without any problems. However when people join my server and I run the /lp editor command to edit permissions, they show me duplicate players.
I think players have to log in at least twice before they get this. It also duplicate the permissions twice like this:

Best regards.

This was very recently fixed in an update. Try downloading the latest version from https://luckperms.net

Ok, thanks it's good.