popup virus

More resources:

Feb 2017 macjack post on dealing with Safari virus warnings [on Mac] - https://discussions.apple.com/message/31415398#message31415398

April 2018 VikingOSX post - https://discussions.apple.com/thread/250597074?answerId=251321863022#251321863022

A Browser Pop-up Scam has Taken Over Safari - https://sites.google.com/site/appleclubfhs/support/advice-and-articles/browser-popup-hijack-safari

About pop-up ads and windows in Safari - https://support.apple.com/HT203987 - "Learn how to block annoying pop-up ads on your iPhone, iPad, iPod touch, or Mac."