OpenBSD's wsmouse (wstpad) driver for touchpads recognizes two-finger scrolling left and right and generates mouse button 6 and 7 events (as well as 4 and 5 for scrolling up and down).
This program listens for those mouse button 6 and 7 events and then generates
fake XF86XK_Back or XF86XK_Forward keyboard events with the XTest
extension.
In at least Firefox, this effectively enables left and right two-finger swipe
gestures on a touchpad to navigate backward and forward.
Since these button events are generated many times along a two-finger swipe,
this program throttles its output and only generates one back or forward key
per 750 milliseconds (configurable with the -i option).
ISC
Run make to compile, and make install to install to /usr/local by
default.
Add /usr/local/bin/tpadnav & to ~/.xsession.
If the 1 second throttling is generating more events than you want, try a
higher -i value (in seconds).
If it's not doing anything, run it with -v to see verbose output.