Assigning to jshin per go/url-spoofs.

> This ŋ (U+014B) is regarded as similar to Latin small letter N, 

Well, the current Unicode data does not. It has to be added to Chrome's
Supplementary list to be regarded as similar.

https://chromium-review.googlesource.com/c/chromium/src/+/919423 is a CL. 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/37747f4a4972e6d44d3f956f8d3a63255ef0941a

commit 37747f4a4972e6d44d3f956f8d3a63255ef0941a
Author: Jungshik Shin <jshin@chromium.org>
Date: Thu Feb 15 06:56:39 2018

Add more entries to the confusability mapping

U+014B (ŋ) => n
U+1004 (င) => c
U+100c (ဌ) => g
U+1042 (၂) => j
U+1054 (ၔ) => e

Bug:  811117 , 808316 
Test: components_unittests -gtest_filter=*IDN*
Change-Id: I29f73c48d665bd9070050bd7f0080563635b9c63
Reviewed-on: https://chromium-review.googlesource.com/919423
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Jungshik Shin <jshin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536955}
[modify] https://crrev.com/37747f4a4972e6d44d3f956f8d3a63255ef0941a/components/url_formatter/idn_spoof_checker.cc
[modify] https://crrev.com/37747f4a4972e6d44d3f956f8d3a63255ef0941a/components/url_formatter/top_domains/test_domains.list
[modify] https://crrev.com/37747f4a4972e6d44d3f956f8d3a63255ef0941a/components/url_formatter/top_domains/test_skeletons.gperf
[modify] https://crrev.com/37747f4a4972e6d44d3f956f8d3a63255ef0941a/components/url_formatter/url_formatter_unittest.cc

Verified on 66.0.3349.0. Thanks as ever!

Verified in 66.0.3350 as well. Thank you for verifying. 

http://xn--istagram-irb.com/  is shown in punycode instead of iŋstagram.com . 

Requesting for merge to M-65 branch. 

The el recorded in comment 6 is simple (adding a few extra mapping entries) and safe. 

This bug requires manual review: Less than 11 days to go before AppStore submit on M65
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

+ awhalley@ (Security TPM) for M65 merge review

I'm afraid the VRP panel declined to award for this one. Thanks for the report, as ever :-)

This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot