Customize Gestures
You can set the Two-finger Tap, Three-finger Tap and Four-finger Tap gestures to perform one of the following commands: switch to the previously used tool, activate the Eraser tool, open the Color panel, Undo or Redo the last command.
Tap the cogwheel button from the Titlebar to open the Preferences panel, and then tap the Customize Gestures button.
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