The code modified the cookies for the site so that the extension authors receive affiliate payment for any items purchased. If the site visited matched a list of ecommerce sites, the developer domain instructed the extensions to insert JavaScript into the visited page. The extensions sent the name of each site visited to the developer-designated site d., along with a unique identifier and the country, city, and zip code of the visiting device. Behind the scenes, company researchers said, the extensions kept a running list of each site a user visited and took additional actions when users landed on specific sites. The five extensions flagged by McAfee purport to offer various services, including the ability to stream Netflix videos to groups of people, take screenshots, and automatically find and apply coupon codes. Google has removed browser extensions with more than 1.4 million downloads from the Chrome Web Store after third-party researchers reported they were surreptitiously tracking users’ browsing history and inserting tracking code into specific ecommerce sites they visited.

Google extensions store