To be truly useful, the new collapsible list feature needs to update the heading (h1,h2 etc) that is rendered within it to reflect the value of the clicked <LI>. Perhaps it should retain the original heading value and append the selection, or maybe not....
I'm sure this was the intent - the old way of showing native lists was unacceptable but the new does not update the heading as the old way did.
So the question is "how do I do this?" (have I missed something in the doco)
Perhaps this feature is just not quite finished yet....