Using the touchpad on my Surface Pro 3 type cover, two-finger scrolling in Firefox and some other programs is completely unusable because moving my finger half a millimetre scrolls down three pages.
In Edge, Explorer, and all Metro apps, two-finger scrolling is normal, but scrolling in Firefox and many other Win32 programs is unusable. Wheel scrolling with a regular mouse is normal everywhere.
This has been a problem for a very long time (years), but I have never been able to figure out why, nor have I found anyone else with this problem. I've gotten used to scrolling with the keyboard and the touch screen, but it's very annoying. I've re-installed Windows from scratch at least once, but nothing changed. None of the touchpad or mouse settings change this behaviour. If I change the "lines per scroll" option to 1, scrolling in Firefox et al. becomes usable although still too fast, but scrolling everywhere else is waaay too slow.
Why is two-finger scrolling so dysfunctional in Win32 programs using the touchpad (trackpad) on my Surface Pro 3, and how can I fix it?