I've found that `localStorage.mouseSensivity = 4` (the default max is 1) seems to set it to about the right amount. However mouse movement is now very jumpy. It seems that individual mouse events are visible and mouse acceleration curves cause very unpleasant behaviour.
Maybe it is something to a high resolution screen, so one CSS pixel is actually quite large?
3840x2160 with 150% Scaling, Firefox on Wayland (KDE) on Arch Linux.
Somehow, the mouse is not just slow but has a hard downtrend. After swiping 5 times left to right and back again. I look at my feet. The downtrend increases with higher mouse sensitivity.
Maybe it is something to a high resolution screen, so one CSS pixel is actually quite large?