Help Can't FullScreen on Chrome on HTC M8 GPE on Marshmallow 6.0?

Can someone please tell me why full screen is not working on Google Chrome browser on my HTC M8 GPE. I'm running Marshmallow 6.0
I went into Chrome settings and checked "fullscreen" but I still don't see it going into full screen, the navigation bar is taking up that space and not going away. Could it be due to Marshmallow update? Much appreciated if someone can help out.