Thank you so much for creating this extension, it seems to be the best solution so far.
I have run into a problem though, which is that the last header that is collapsible will collapse all other headers into it.
Eg. I want to collapse h5's, meaning that every element that is sub-h5 level should collapse (h6 and p elements). Instead, the extension will collapse everything under the h5, even if there is an h2 coming. This makes it practically unusable for anything other than h2s. Any thoughts on how to fix this? Thanks