[bigato]

Scratch my post above, I made a better example:

https://pastebin.com/raw/9D02J80s

[lukastyrychtr]

Unfortunately, this is missing the semantic metadata about the fact that it's a tree. It might be fine in some cases, but in general you would want to add some Aria attributes. But i'm not sure whether you could generate the entire thing server-side.

[jakearmitage]

Thank you, that's enlightening.