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My iMac has a loose bot taking over my safari shortly after I turn on. It interrupts now even when I’m in a “new private window.” For a few days using a private window prevented it. I have read several online users remedies to delete the troublemaker but they are too technical for me to understand and/or I fail to locate the described command points. A run of the anti-malware for Mac does not find this bug. My iMac is ten years old. Will have to take it to an Apple store to have it sorted. Help, please.