Google Chrome 69.0.3494.0 (Official Build) dev (64-bit), Firmware Version	Google_Eve. 9584.160.0

Steps to reproduce: 
# Flip convertible ChromeVox into tablet mode
# Turn on ChromeVox by holding both hardware volume keys for 5 seconds 
# Invoke the Customize and Control Chrome menu 
# Use the menu navigation gesture of one finger up or down repeatedly
Expected: gesture always recognized 
Actual: gesture only recognized about 50% of the time