Google Chrome Incognito Mode Can Still Be Detected
With the release of Chrome 76, Google fixed a loophole that allowed web sites to detect if a visitor was using Incognito mode. Unfortunately, their fix led to two other methods that can still be used to detect when a visitor is browsing privately.
Some web sites were using Incognito mode detection in order to prevent users from bypassing paywalls or to give private browsing users a different browsing experience.
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When Google made it so that Incognito mode uses a temporary filesystem using the computer's RAM, it opened up a new method of detecting it based on the amount of storage set aside for the internal filesystem used by the browser.
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As Chrome switched to a memory filesystem in Incognito mode, it is now possible to detect private browsing by measuring the speed of writing to the filesystem.