I think this was a problem or bug caused by Ubuntu installed on Macbook. However this is a new feature of Ubuntu supporting multitouch devices. Occasionally, when I placed my two finger (I didn't realize the third) on Mac touchpad, the application switcher appears and select a window app from switcher. It was annoying me at the first, but when I know this is a new feature, I realize my fault (my third finger erratic touch the pad), and get benefit of it.
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App switcher appears erratic on Ubuntu on Mac |
Yes, this was three fingers tap followed by hold to switch between app windows, not two fingers. The explanation is given below. Yatta! Canonical and Ubuntu are struggling hard to make multitouch devices working perfectly.
The best solution is to adapt it, not to disable it. By time it will be improved and here is the current list: