https://help.ubuntu.com/community/MouseCustomizations

oder
xmodmap
keycode $wheelbutton = Prior
keycode $wheelbutton = Next


find map:
xmodmap -pke
/usr/include/X11/XF86keysym.h
https://wiki.archlinux.org/index.php/xmodmap

system wide auto start:
/etc/X11/Xsession.d/