When I create a note in one world, it appears on all my worlds.
I'm assuming this is supposed to be "global" behaviour, but it's happening even when global is off.

Using 1.20.1-1.3.0-forge

I'm having the same problem on Fabric,, version 1.20.4-2.1.0-fabric

This should be fixed in the latest versions for 1.21. Feel free to reopen if it persists.