The ability to show only selected Features on a Class or Block symbol in diagrams is very useful. It enables you to show only those Features that are relevant to that diagram, a bit like a collaboration.
But if you add a new Feature elsewhere, that diagram will then also show the new Feature, which might not be relevant ("graphical coupling").
It would be nice to be able "freeze" the compartments in selected diagrams so that their Class and Block symbols to not show any additional Features unless explicitly chosen on the symbol in that diagram.