I think that this addon should be reviewed to be part of the “Recommended” addons.
It really change browsing and it is a simple and really natural way of using gestures for anyone.
By the way, I’m not related in any ways with anything regarding this addon except for utilizing it on Chrome based browsers cause it has been recommended there. Though, Chromium based browsers are my secondary browsers, so I wish it could be check for Firefox prior using it due to the kind of permissions needed for such addons.