Ok, I played with #firefox57 yesterday evening and... I have mixed feelings. It is faster, but so what? 56 is already fast enough. Does it really make a difference to render a page in 3s rather than in 5? I save hours in the long run, I get it, but I loose tens of them by not being able to manage my tabs poperly. How people do that without extensions like tabmix plus or panorama? How can people have 50 tabs open and find their stuff? Please enlighten me.