The touch docker is for people with 2:1 devices without real buttons.
It mimics the wacom tablet buttons/rocker switch, a bit. The top 6
buttons and the "rocker switch" buttons aren't configurable, the
other 8 buttons can be configured by adding a line to kritarc

touchdockermapping=action1,action2,action3,action4,action5,action6,action7,action8

Note that the default configuration is useful, but shows a bad lack
of icons.

To figure out: how to toggle modifiers, like shift, ctrl and alt,
so pressing buttons configured with those keys actually apply
the modifier keys to all events until toggled off.