I'd advise against using d3.selectAll() in the context of Observable, because it will select across the entire document (like document.querySelectorAll). Instead, you can name your svg cell via the toolbar at the bottom, then reference it directly, e.g.: d3.select(mySvgCell).selectAll(...)

But even then it would still not solve my original question. Am I correct?

Yes, this was more of an aside. :)