Hi HN! I built a Chrome extension that generates recursive/nested "tooltips" upon hovering over links, images, pdfs, and unlinked citations like DOI, arXiv, PMID, etc.. I was playing Europa Universalis V and realized I could implement the same system but for everything just by using Wikipedia as a truth-source and pairing it with an LLM. It works especially well on hackernews itself, I frequently will hover an article about something I don't understand, and I can fill in all my knowledge gaps just by following the thread of nested keywords. It reads the page you're on, and the page you're hovering over, and then acts as a gel between them so the tooltip is always contextualized and doesn't need to hallucinate new information.
It's free and open-source in lineage with Ted Nelson and Project Xanadu's hyperlinks, I think eventually this UX mechanism could be an open web standard with sufficiently democratized compute/inference. https://github.com/alaskahoffman/portaltext