App Version: 71.0.3578.14 Beta
iOS Version: 12.0, 11.4.1, 10.3.3
Device: iPhone XSMAX

Prerequisite: 
1. Enable ‘#out-of-web-fullscreen’ flag from chrome://flags
2. Enable ‘#browser-container-fullscreen’ flag from chrome://flags

Steps to reproduce:
Go to qq.com
Scroll the webpage


Observed results:
Nav bars in webpage are misplaced when page is scrolled to fullscreen.

Expected results:
Nav bars, headers of webpage should be static when page is scrolled.

Number of times you were able to reproduce: 5/5
Bug reproducible after clean install: Yes
Bug reproducible after clearing cache and cookies: Yes
Bug reproducible on Chrome Mobile on Android: Not tested
Bug reproducible on Safari/Firefox: Firefox: No, Safari: No
Bug reproducible on current stable build (App Version, iOS Version): NA on M69 
Bug reproducible on the current beta channel build (App Version, iOS Version): Yes on M71 New Feature
Type-bug-regression- New Feature
Link to video:
https://drive.google.com/file/d/1u4aoCz531r-6jn-jtuCOQIJzHx8yK6qC/view?usp=sharing