Currently the behavior is exactly as described in your post - the item (except the expand/collapse button) only navigates (does not expand or collapse itself) when having a navigateUrl set. And even having navigateUrl when clicked on the little button on the far-right of the item, it only expands/collapses the item.
Maybe I didn't understood your question, so if that is the case, please explain in a bit more detail what is the behavior that you have troubles implementing.
Hope that soon we will resolve this!
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