Chrome Version       : 53.0.2785.143 
URLs (if applicable) :mail.yahoo.com
Other browsers tested:FireFox
  Add OK or FAIL, along with the version, after other browsers where you
have tested this issue:
     Safari:
    Firefox:49.0.2
         IE:

What steps will reproduce the problem?
(1) Just trying to get mail from mail.yahoo.com
(2)
(3)

What is the expected result?
Normal login. 


What happens instead?
Error screen that indicates:
Your connection is not private

Attackers might be trying to steal your information from us-mg5.mail.yahoo.com (for example, passwords, messages, or credit cards). NET::ERR_CERTIFICATE_TRANSPARENCY_REQUIRED
 

Please provide any additional information below. Attach a screenshot if
possible.

I have used Chrome and Chromium for years and have not encountered this problem. It seems to be exclusive to Chrome/Chromium since FireFox operates normally. I have tested Chrome on Windows 10 and Chromium on Linux Mint 18. Both show the same result.

No issues with network settings are involved since FireFox works. And, anti-virus issues are not involved on Linux. It is a product related issue.