EDIT

copied from #6806

It looks like multiple usage of 1 feature in the same feature tree is currently not/now supported. If I e.g. select a feature that is already in the feature tree nothing happens. Is this on purpose?

Maybe needs discussion. There are usecase where we want multiple usage, e.g. for structures in a structure tree (feature tree might become term tree in future). Maybe we need a flag to allow or not allow multiple usages, depending of the type of feature tree)