App Version: 68.0.3440.6 Beta
iOS Version: 11.3.1,10.3.3
Device: iPhone,iPad

Precondition:
1.Enable “web-error-pages” from chrome://flags

Steps to reproduce:
  1. Launch chrome & goto facebook.com.
  2. Disable the Wifi
  3. Goto whatever.com in the same tab
  4. Tap on back arrow and navigate back to facebook.com
  5. Enable Wifi
  6. Tap on Forward arrow
  7. User is navigated to youtube.com 
  8. Tap on back arrow blank page is displayed 
  9 .Tap on back arrow and go back to NTP
 10. Tap on Forward arrow

Observed results: 
“about:blank?” Url is displayed in omnibox.

Note : Works fine on Disabling the flag “web-error-pages”

Expected results: 
Website url should be displayed

Number of times you were able to reproduce: 3/5
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 M66 and 67
Bug reproducible on the current beta channel build (App Version, iOS Version): Yes in M68

Link to video/image:  
Image :
https://drive.google.com/file/d/18j59336gRnIUuq0m7ZxzKZLWuVM_gK3Y/view?usp=sharing

Video :
https://drive.google.com/file/d/1RSAVLOE0mQqQTqjvfXJLGijCIvFR6YIf/view?usp=sharing