This is great! Howdya do that?
Am I misunderstanding the idea if I say: what you are implementing are web annotations, but only for a specific website? If not, I’d say hypothes.is already offers that functionality and probably in a better way. Except that hypothes.is is not so great at the discussion part. It’s good for annotations and a couple of follow up replies, but when a fully fledged discussion evolves, discourse would be so much better.
I’d love to see a better integration between discourse and hypothesis. How well does that fit what you are doing?