I'm using this now, and it does feel like it's much improved!
More: Firefox 57: Good news? It's nippy. Bad news? It'll also trash your add-ons (10. November 2017)First the good news. Firefox 57 is faster, quite noticeably so, thanks to improvements to what Mozilla calls Project Quantum. Quantum encompasses several smaller projects in order to bring more parallelisation and GPU offloading to Firefox. That's developer speak for using more of that really fast GPU you've got. And again, the results are noticeable (some of them have already rolled out).