Single-pixel images, embedded in the emails we receive, allow senders to note if that email has been ignored, opened (with an exact timestamp) and even forwarded. There are several free ways to prevent that tracking pixel from loading and reporting back. The first option, of course, is preventing the images in emails from auto-loading altogether. Though this alters aesthetics, it drastically increases privacy measures. Other tools, like the free, open-source Ugly Email extension and free Trocker extension offer calculated control, displaying an icon beside an email that alerts users to a pixel within. Some of these extensions even expose tracked links. To learn how to disable auto-loading or download any of these extensions, head over to Wired.
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