No, this never got implemented and I don’t foresee any work being done on this going forward. Mostly I’m just going to try to keep FoldingText working if it breaks in future OS update.
Thanks for keeping it going. As much as I’d like to see new features, I depend so heavily on FoldingText as a note and research-organization tool that I’m always afraid it’ll break for good. I haven’t found anything remotely comparable.