Windows 10 build 10166

Release date: 07/07/2015

New web platform features

  • localhost loopback is now enabled by default. You can toggle localhost by navigating to about:flags.
  • Improved support for about:flags in locales other than en-US
  • Bug fixes

Known issues in build

Microsoft Edge has a new app ID that will cause any favorites, cookies, history and Reading list items that you had saved in “Project Spartan” from previous builds to be lost after upgrading. If you want to keep these, make sure you back up your favorites before upgrading to Build 10166. To save your favorites, follow these steps before upgrading:

  1. Copy your favorites from %localappdata%/Packages/Microsoft.Windows.Spartan_cw5n1h2txyewy/AC/Spartan/User/Default/Favorites
  2. Save them to %userprofile%/Favorites.
  3. After upgrading to the next build open Microsoft Edge, choose Settings, and you’ll see an option to import favorites from another browser. Choose Internet Explorer to import the favorites you saved in your %userprofile% directory into Microsoft Edge.

Learn more about this release on the Windows blog

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