* Open a pdf in presentation mode
* Set Preferences->Presentation->Tap Navigation to 'Forward/Backward'
* Touch the right half of the touchscreen
* Result: the next page is shown
* Touch the left half of the screen
* Result: the previous page is shown
* Set Preferences->Presentation->Tap Navigation to 'Forward'
* Touch the right half of the touchscreen
* Result: the next page is shown
* Touch the left half of the screen
* Result: the next page is shown
* Set Preferences->Presentation->Tap Navigation to 'Off'
* Touch either half of the touchscreen
* Result: nothing happens