There is a feature to swipe away notifications that pop up by using a two-finger swipe from left to right while hovering over the notification. I've read about it on multiple websites (http://osxdaily.com/2012/09/05/dismiss-notifications-os-x-quickly-swipe/), and seen this work on friends' computers, but I am unable to make it work. Is there anyone else who has had this issue, and know how to solve it? I can't find anything in trackpad settings or in notification center settings. I thought it might have to do with the fact that I was using Better Touch Tools, but I closed that and restarted my computer to no avail. I am using a Mid-2011 13" Macbook Air.