Remove "Do you want to download f.txt.js" pop-up virus from MacMac adware and browser hijackers tend to be treated synonymously these days, because most browser-targeting threats are hybrid and call forth a mix of noxious symptoms. If a sketchy ad is recurrently popping up in the middle of web surfing sessions on different websites, it means that the root cause for the issue resides in the system rather than the web services being visited.
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Remove "Do you want to download f.txt.js" pop-up virus from Mac