FF is pretty crap these days (as a lifelong FF fanboy). I'd hesitate to use it except for HN where its low speed and security are part of the experience.
I don't understand comments like this. Chromium grinds to a crawl and even locks up with more than a handful of tabs, and its developers are deliberately adding new security vulnerabilities.
The review process for new web APIs in general is pretty shoddy and not terribly concerned with security (eg Canvas). However I was specifically referencing this of the past few days: https://news.ycombinator.com/item?id=36910978