How to share same instance across multiple trees?

[ParadiseFallen]

Hi/ i have kinda Window store (window that can be closed and dragged).

So i has Sidenav and Messages models. (ViewModels thing). So i need to pass Window to Sidenav and messages but got error
Uncaught Error: [mobx-state-tree] Cannot add an object to a state tree if it is already part of the same or another state tree. Tried to assign an object to '/window', but it lives already at '/window'

[EmilTholin]

Hi @ParadiseFallen!

Do you think you could include a minimal, reproducible example in e.g. a CodeSandbox? It's difficult to say what might go wrong without seeing some code.