Google plans to fix a flaw in Chrome's Incognito mode that allows websites to easily detect it and block people who use it.

Slated for an upcoming version of Chrome, a new option will try to resolve a loophole that has long existed in Incognito mode, as reported by 9to5Google. Incognito mode works by disabling Chrome's internal FileSystem API so that cookies and other data aren't saved. But websites can easily detect when this API is disabled, which then tells them that Incognito mode is turned on. The fix would instead create a virtual file system in memory and then delete all traces of your activity after you leave the site.

Incognito mode, also known as Private mode, prevents the browser from saving your cookies, history and other data that websites and advertisers can use to track you. The feature is one way for people to better protect their privacy on the Web. But many websites serve up paywalls that let you view a limited amount of information for free and then insist that you pay or subscribe to see more. Such websites rely on cookies and trackers to determine your status so they know when you've reached your free limit. Since Incognito mode disables cookies, some of those sites now simply block you if they detect it.

SEE: Make Your Browser Work for You with the Best Chrome Extensions

Using Chrome, you can see how some websites prevent you from accessing content in Incognito mode. Launch Chrome. Click on the three-dot icon in the upper right and select New Incognito window. Open the website for the "Boston Globe" or "MIT Technology Review." Click on a link to an article. A message pops up saying that "You're using a browser set to private or Incognito mode." To continue in Incognito mode, your only options are to sign in if you're a subscriber or sign up for a new subscription.

Described by Chrome developers in online documentation about source code changes, the fix could arrive as soon as Chrome 74, two major versions away from the current release. The feature may then be enabled by default in Chrome 76. But creating a virtual file system may just be the initial step. Based on an internal document discovered by 9to5Google, the ultimate goal is to kill off Chrome's file system altogether, especially since its only purpose seems to be to help websites detect Incognito mode.

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  • Google is aiming to fix a flaw in Chrome's Incognito mode that allows websites to detect it and block users who have it turned on.
  • The fix could come as soon as Chrome version 74 and then be enabled by default in version 76.

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Lance Whitney is a freelance technology writer and trainer and a former IT professional. He's written for Time, CNET, PCMag, and several other publications. He's the author of two tech books - "Windows 8 Five Minutes at a Time" and "Teach Yourself VISUALLY LinkedIn."