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The upgrade addressed a number of criticisms faced by Windows 8 upon its release, with additional customization options for the Start screen, the restoration of a visible Start button on the desktop, the ability to snap up to four apps on a single display, and the ability to boot to the desktop instead of the Start screen. Windows 8's stock apps were also updated, a new Bing-based unified search system was added, SkyDrive was given deeper integration with the operating system, and a number of new stock apps, along with a tutorial, were added. Windows 8.1 also added support for 3D printing, Miracast media streaming, NFC printing, and Wi-Fi Direct.

What main feature was added back to the desktop?
a visible Start button