Pinchy is a simple add-on to set some gesture-related preferences. These prefs work on Mac computers with trackpads.
- pinch in == zoom in
- shift + pinch in == close tab
- pinch out == zoom out
- shift + pinch out == toggle full screen
- shift + 3-finger swipe left == previous tab
- shift + 3-finger swipe right == next tab
Once this add-on has been installed and pops up a panel notifying you it’s done, you may uninstall the addon. The prefs are set!
Source of these gestures was found on the excellent http://t.tal.by/post/95428783/changing-firefox-gestures