Show failed tests only

It's quite hard to work with large test files (200+ tests) when only few of them fail. Each time I refresh the page I got to scroll through the whole list to see which tests are red. It feels like a nightmare after a couple of hours of debugging with very few red islands amid the vast ocean of green. Not to mention how the mouse scroll feels about it.

So I propose "Show failed tests" button. One "Click" and everything's simple.