@spacecadet Your structure to navigate the #bookmarks is the same structure I came up with to navigate (local) files via tags.
For that, I came up with the name #TagTrees. So there is a name for that structure and you may use that as well. 😉
Background on TagTrees and file management: https://karl-voit.at/tagstore/en/papers.shtml with my PhD being the most important, because it summarizes the concept: https://karl-voit.at/tagstore/downloads/Voit2012b.pdf
Related to file management: I used my experience from #tagstore and created that method around #filetags: https://karl-voit.at/managing-digital-photographs/
HTH
