Unexpected crash when going from compact to regular size class or when restoring state for a new window.

I'm trying to implement the new sidebar for iPadOS 14, and am using a three column layout when creating a new window from one such view or when moving from compact to regular size classes, the app crashes with the following error message:

'Lost track of navigation controller for Supplementary column when expanding <SplitViewController class name>'

What is the best way to tackle this error?
Unexpected crash when going from compact to regular size class or when restoring state for a new window.
 
 
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