I run Firefox on a laptop with a touchscreen, but always use a mouse.
The following code determines which event to listen for on the button, and selects the
touchend event on any device with a touchscreen.
var clickEvent = !!("ontouchstart" in window) ? "touchend" : "click";
Unfortunately, this means it's not listening for clicks so the button just doesn't work at all!
Could we change the code to just listen for either event?
var clickEvent = "touchend click";
You'll get double-ups on devices that have both, but that doesn't really matter as you're just generating a new password anyway.