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Go to Trackpad in System Preferences, More Gestures tab, and change "Swipe Between Pages" to "Swipe with Two or Three fingers". This will also allow you to swipe back/forward in the Finder, iPhoto and other apps again with a three finger swipe. I think Swipe Between Full Screen Apps will automatically change to a four finger swipe when you do this. If not, change it manually.
 
Go to Trackpad in System Preferences, More Gestures tab, and change "Swipe Between Pages" to "Swipe with Two or Three fingers". This will also allow you to swipe back/forward in the Finder, iPhoto and other apps again with a three finger swipe. I think Swipe Between Full Screen Apps will automatically change to a four finger swipe when you do this. If not, change it manually.

then you lose the three finger drag :eek:

it auto disables it
 
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