How to bring back multi-touch gestures after it crashes without reboot? After a clean install of Yosemite, multi-touch gestures have stopped working on two occasions on my Macbook Pro 2011. Each time, the symptoms are the same:


Gestures stopped working both built-in trackpad and bluetooth trackpad.
BetterTouchTool still works. Restarting, stopping BTT doesn't help.
Hey, at least two-finger click -> right click still works.


I've tried the following:


Toggling trackpad configurations doesn't bring back the gestures.
Disconnecting, reconnecting, removing bluetooth trackpad from list of bluetooth devices doesn't work.


Restarting solves the problem. However, a restart in my case is a time-consuming process. It involves properly shutting down apps, dismounting network storage, disconnecting VPN, etc - only to revert all the steps again on startup.

I suspect the process interpreting multi-touch crashed when the malfunction happened. CPU was quite busy at both point. So I wonder if there is a process I can call up when it happens again, to avoid restarting the machine.
Type killall Dock in Terminal.

In my case, only Mission Control gestures had stopped working (three finger swipe left/right to switch spaces, three finger swipe up for overview, mission control etc).