You have to actually toggle to see it but IMO it massively improves how scrolling feels.
There are a few more scrolling-related options out there on the net if there's a particular "feel" you want to go for. https://github.com/yokoffing/Betterfox/blob/main/Smoothfox.js provides a couple you can try out, and most of these custom scrolling options use msdPhysics as a baseline.
I just switched from Chrome today and I was wondering how to improve the scrolling (it felt heavy and slow). This setting seems to have worked wonders! Thanks!