Platform Development • Re: e10s support question

Could there be much more to fast JavaScript crunching than just multi-process? That part certainly prevents hiccups and additional slow down, but otherwise doesn't improve base speed. SeaMonkey could still get notably higher scores on Speedometer and generally felt a bit more fluent last time I tried it compared to UXP. And classic extensions still break left and right with e10s, like what I remember from trying roytam1's Serpent years ago.