App Version: 65.0.3325.53 Beta
iOS Version: 11.2.2
Device : iPhone,iPad

Precondition :
Have few accounts saved.

Steps to reproduce : 
1. Launch chrome and Sign in to chrome.
2. Tap on Menu > Settings > Privacy.
3. Tap on Learn More.
4. Tap on Profile icon.
5. Tap on Manage accounts.
6. Tap on Go Incognito. 
 
Observed results:
Bad Request error is displayed in incognito mode.

Expected results:
Error page should not be displayed.

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 Dolphin/Safari/Firefox: Safari : NA
Bug reproducible on current stable build (App Version, iOS Version): Yes in M64
Bug reproducible on the current beta channel build (App Version, iOS Version): Yes in M65

Link to video :
https://drive.google.com/file/d/1wqwFsdFQcULYAt1rgCjmZAOs7j0FEPB0/view?usp=sharing