@bobjonkman so, if I don't let my email client produce any notifications, I'm sure my browser coudln't display them either. (I never let any mail program produce notifications - I actively go to see if there's anything new I should pay attention to. Even on my phone.) Antivirus - sure: if it does find something during a regular scan it certainly should notify me - but why would it use the browser for that? And such a notification from the AV program would surely have the style and "signature" of that program - anything different is by definition suspect.