Chrome Version : 66.0.3359.26 (Official Build) b3471a2c378d1cfc5be97bb38b9c32038d1aef14-refs/branch-heads/3359@{#146} 32/64-bit
OS : Windows(7,8,8.1,10), Linux(14.04 LTS)and MAC(10.12.6,10.13.1,10.13.4)

Test URL:https://www.thesun.co.uk/news/5783095/sir-william-henry-perkin-google-doodle-aniline-dye-purple/

What steps will reproduce the problem?
1. Launch chrome, navigate to above URL 
2. Observe the Page.

Actual Result : Down arrow of drop-down is distorted.

Expected Result : Down arrow of drop-down should not be distorted.

This is a regression issue, broken in M-65 and providing the bisect results using per-revision script :
Good Build : 65.0.3309(Revision :526410)
Bad Build :  65.0.3310.0(Revision :526575)

You are probably looking for a change made after 526495 (known good), but no later than 526496 (first known bad).
CHANGE-LOG URL:
The script might not always return single CL as suspect as some perf builds might get missing due to failure.

https://chromium.googlesource.com/chromium/src/+log/5b2de20541d2b08bf64e81804b538eb4d03a4e21..e4d6d0b50ec2e40aabe6a8c9928f512101771bb1

Suspect:https://chromium.googlesource.com/chromium/src/+/e4d6d0b50ec2e40aabe6a8c9928f512101771bb1

@Stephen White: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Note : 
1.Issue is reproducible on today's Dev #66.0.3359.27(PGO), Stable #65.0.3325.146 and Beta #65.0.3325.124 build.
2.Issue is not seen on Linux OS
 
 

Deleted: ACTUAL.mov 5.5 MB

	ACTUAL.mov 5.5 MB View Download

Deleted: EXPECTED.mov 4.1 MB

	EXPECTED.mov 4.1 MB View Download

Chrome Version : 66.0.3359.26 (Official Build) b3471a2c378d1cfc5be97bb38b9c32038d1aef14-refs/branch-heads/3359@{#146} 32/64-bit
OS : Windows(7,8,8.1,10)and  MAC(10.12.6,10.13.1,10.13.4)

Test URL:https://www.thesun.co.uk/news/5783095/sir-william-henry-perkin-google-doodle-aniline-dye-purple/

What steps will reproduce the problem?
1. Launch chrome, navigate to above URL 
2. Observe the Page.

Actual Result : Down arrow of drop-down is distorted.

Expected Result : Down arrow of drop-down should not be distorted.

This is a regression issue, broken in M-65 and providing the bisect results using per-revision script :
Good Build : 65.0.3309(Revision :526410)
Bad Build :  65.0.3310.0(Revision :526575)

You are probably looking for a change made after 526495 (known good), but no later than 526496 (first known bad).
CHANGE-LOG URL:
The script might not always return single CL as suspect as some perf builds might get missing due to failure.

https://chromium.googlesource.com/chromium/src/+log/5b2de20541d2b08bf64e81804b538eb4d03a4e21..e4d6d0b50ec2e40aabe6a8c9928f512101771bb1

Suspect:https://chromium.googlesource.com/chromium/src/+/e4d6d0b50ec2e40aabe6a8c9928f512101771bb1

@Stephen White: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Note : 
1.Issue is reproducible on today's Dev #66.0.3359.27(PGO), Stable #65.0.3325.146 and Beta #65.0.3325.124 build.
2.Issue is not seen on Linux OS
 
 

Deleted: ACTUAL.mov 5.5 MB

	ACTUAL.mov 5.5 MB View Download

Deleted: EXPECTED.mov 4.1 MB

	EXPECTED.mov 4.1 MB View Download