Graph is linked to objects in external map error

I am using Landmass plugin brush with World Composition level, and when I try to save it is throwing me an error. The plugin works fine when using without World Composition.


I’m having the same exact issue with World Composition

A workaround I found was selecting the landmass manager in the world outliner, cutting it, then making the level that isn’t saving my current level, then pasting it and saving all levels again. I don’t completely understand why the manager can’t be in the persistent level, but this fixes it.