Comment 49 for bug 1368402

(In reply to dinar from comment #20)
> in debian 10, i solved this running
> nano /usr/share/X11/xorg.conf.d/40-libinput.conf
> man libinput

This worked for me....doing nothing else but adding
Option "NaturalScrolling" "1"
to all the mousy devices in
/usr/share/X11/xorg.conf.d/40-libinput.conf

thanks @dinar!