Open Terminal.app and execute the following command-lines one by one:
defaults write com.apple.AppleMultitouchTrackpad DragLock -bool true
defaults write com.apple.AppleMultitouchTrackpad TrackpadThreeFingerDrag -bool true
Open Terminal.app and execute the following command-lines one by one:
defaults write com.apple.AppleMultitouchTrackpad DragLock -bool true
defaults write com.apple.AppleMultitouchTrackpad TrackpadThreeFingerDrag -bool true
