Nested ForEach two-way bindings - Index out of range

I'm almost there, but again, no.

I get the source of truth to work on one level, but almost without exception I have created something that only consists of one level.

I have a github example to make it easy to reproduce the scenario. I hope it´s me and not a feature of SwiftUI :)

Nested ForEach two-way bindings - Index out of range
 
 
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