Version: 66.0.3358.0 (Official Build) Revision16fdb6c5f5d6e5779983e253b5f7c8bdd1cac610-refs/heads/master@{#539998}(64-bit)
OS: Mac OS X(10.12.6,10.13.1,10.13.4)

What steps will reproduce the problem?
1. Launch chrome and observe 'Avatar' icon on top RHS of browser
 
Actual: 'Avatar' icon appears faint than expected
Expected: 'Avatar' icon should be seen properly

This is regression issue, broken in ‘M 66’ and below is the bisect info :
Good build: 66.0.3357.0 (Revision: 539660).
Bad build: 66.0.3358.0 (Revision: 539998).

You are probably looking for a change made after 539742 (known good), but no later than 539743 (first known bad).

CHANGELOG 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/f3b3701c383ab247d1b737727b2546f05d2d326f..f43dc78128f4977252d8eb3ab2f1d3302f9562cb

Suspect : https://chromium.googlesource.com/chromium/src/+/f43dc78128f4977252d8eb3ab2f1d3302f9562cb

From the CL above, assigning the issue to the concern owner 

@pbos- 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. This issue is not seen on Windows (7,8,8.1,10) and Linux (14.04 LTS) OS
2. This issue is seen on both the cases i.e with/without enabling flag "--site-per-process"

Thanks!
 

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