App Version: 69.0.3497.70 beta
iOS Version: 11.4.1, 12 beta 10
Device: iPhone, iPad
URL: 

Steps to reproduce:
  1.  Launch chrome beta
  2.  Switch to incognito mode
  3.  Open a new tab in tab grid
  4.  Open more than 10 tabs and switch to tab switcher mode couple of times

Observed results:
At Step 3:  Notice that white screen is displayed on tab while the tab is animating to full screen (Video1).
At Step 4:  Notice that white screen is displayed on tabs while the existing tabs are animating to tab grid mode (Video 2).

Expected results:
White screen should not be displayed while switching back and forth to tabswitcher mode.

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: NA
Bug reproducible on Safari/Firefox: Firefox: NA, Safari: NA
Bug reproducible on current stable build (App Version, iOS Version): NA on M68
Bug reproducible on the current beta channel build (App Version, iOS Version): Yes on M69

Link to video/image:

Video 1:  https://drive.google.com/file/d/12kDQh1Uh-FM4YuJxkXqsWzVU8EMMfpTC/view?usp=sharing

Video 2:  https://drive.google.com/file/d/1yhB8uLvlzOyEM9hU-YLDgxmM5Ela04zG/view?usp=sharing