How to remove "This Update requires an action" popup virus from MacWhen an alert pops up during a web surfing session on Mac, it can be a clue suggesting that something went wrong with the browser. Given that the system is unlikely to display intrusive warnings, such an encounter is probably a sign of adware activity affecting the user’s Internet routine. For instance, in the case of “This Update requires an action” popup in Safari and other browsers, the root cause is a virus called TapuFind or Chill Tab.
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How to remove "This Update requires an action" popup virus from Mac