Days before Christmas, at the height of the last-minute holiday shopping rush, an ominous message appeared on Amazon.com. It warned shoppers who used a popular browser extension called Honey that the service, which promises to track prices and discount codes, was “a security risk.” “Honey tracks your private shopping behavior, collects data like your order history and items saved, and can read or change any of your data on any website you visit,” the message read.

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