Comment 17 for bug 410636

Patrik Nilsson (nipn): laptops has switches too, old rusty switches, which can be replaced =) If it's not touchpad gesture.
Actually I can reproduce it easily with Eclipse with new mouse. In project list, move mouse over project name and hold and release right button while moving mouse to the right fast (just a little shake of a hand is enough with sensitive mouse) and you get menu highlighted and auto selected fast. Not sure if it's gtk releated though.