And the recent buzz about a concurrent engine shows how much slower. When you have 300%+ headroom just by uncoupling your execution strategy from an unnecessary global lock no one else has, you are not "speeding up". You are "catching up."
I have a Surface Book, a recent Macbook Pro, and homebuilt Windows machine with components sourced from 2015's crop with an eye towards performance. Even if it were the case that I was using older hardware, this wouldn't exactly be a good story for Firefox.
Firefox is sluggish on every machine, and consistently feels like the slower paint. I understand the synthetic benchmarks are not so distant, but we don't interact with browsers at the level of Sunspider benchmarks. We interact at the level of full dom renders to screen, first clicks available, scrolling and repainting performance, tab open and close time, and startup time.
Firefox has never been a positive experience for me on those on anything but the very oldest of Linux boxes, and quite frankly I've written off the entire X11/Linux desktop environment as a tire fire with people trapped inside.
Glacially slow.
And the recent buzz about a concurrent engine shows how much slower. When you have 300%+ headroom just by uncoupling your execution strategy from an unnecessary global lock no one else has, you are not "speeding up". You are "catching up."