Scrolling with touchpad is too fast

[alexheretic]

whenever I scroll with two fingers on the touchpad, after I stop scrolling it jumps upward ~50 pixels or so. This happens on all the screens I've tested: the F1 screen, the F2 screen, and the code editor (when there's enough code to scroll through it). Scrolling with the mouse wheel, or with alt+page up/down, works fine.

Also, scrolling with the touchpad is way too fast; it would be more useful if it scrolled around half as fast, or maybe a quarter as fast.

I'm using Ubuntu 18.04