HTTP/2 Server Push was supposed to solve the waterfall issue. Unfortunately: <a href="https://news.ycombinator.com/item?id=32522926">https://news.ycombinator.com/item?id=32522926</a> (Chrome) and <a href="https://news.ycombinator.com/item?id=41464334">https://news.ycombinator.com/item?id=41464334</a> (Firefox).