Companies have a tricky new way to track your movement across the web

Researchers at Princeton have uncovered a new web-tracking method that's nearly impossible to block. It's called "canvas fingerprinting," and can potentially follow users between sites even if they've disabled more conventional methods like cookies and aren't logged into Facebook. Instead, the tactic works by asking the browser to draw a hidden image, and using that image to track the unique properties of the browser. Researchers found the tactic being used on five percent of the top 1000 sites ...