On stable release 59.0.2 at the time of review.

Worked great when it works, but it seems to have the right click button held on even after gesture is complete. So when I scroll up or down, it zooms in and out until I press the right click button again. It seems to be linked to rocker gestures and wheel gestures; with both off there is no issue. This is also a problem in a similar add-on called Gesturefy, but the frequency of 'error' is greater with this add-on.

I never had this problem with the original FireGestures; maybe this is API related.

Edit: Found out that this is a conflict between Foxy Gestures and Zoom Page WE, so if anyone has the same problem then you'd have to disable right-click and scroll function in Zoom Page WE so there is no interference.