Mail.ru’s main page, I was told, once was carefully designed in such a way that it fit everything in a single screen (which, to be sure, is quite an achievement). The inbox also also used to be fairly fast. Not breathtakingly fast, but decent. I heard their backend team was pretty experienced, and that they were using Go for performance reasons. Apparently the same doesn’t go for their frontend team. About a week or so ago they rolled out a new inbox, which is simply horrendous. It takes several seconds to load, on a laptop and a good network connection, because it does something dreadful with javascript (here's the trace):
There’s a lot of javascript going on in this trace, that's for sure. The widest peak took about 700ms to complete. And even after loading the page, every ticking or unticking of a single email causes a burst of javascript activity about 40ms long.
It’s unbelievable how low they’ve fallen.
