Instead, the add-on grabs the Google account password, encrypts it, then saves a partial "thumbnail" of the result to Chrome's local storage on the device. Later, Password Alert compares that thumbnail to the passwords entered on other sites: If they match, the warning flag goes up.
While Password Alert is optional at this point, Google could easily roll the functionality into the browser down the line. The Mountain View, Calif., company has done that before, most recently this year when it overhauled Chrome's bookmarks manager about a year after first offering the new design in an add-on.
Password Alert can be downloaded from the Chrome Web Store and installed into the browser on Windows, OS X and Linux.
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