I just realized that in Google Chrome, Version 55.16.2883.75, when you view the WebApp in full screen mode, it will show extra 2 buttons on the bottom of the screen. Please see attached screen shot.link text
This only happens in Google Chrome but not Firefox. I had also attached the test project for your perusal.
Thanks for your reply. I am still using Windows 7 32 bits. Maybe I will test on other computers with different OS to see whether can I replicate this issue.