Windows 10 build 9879

Windows 10 build 9879 is the third officially released Technical Preview build of the original release of Windows 10. It was released to Windows Insiders in the Fast Ring on 12 November 2014 and to Windows Insiders in the Slow Ring on 25 November 2014.

New features and changes

 * Battery icon is now thinner and flatter in appearance.
 * Action Center was renamed to Security and Maintenance.
 * Feedback button (in the form of a smiley face) has been added to Internet Explorer 11.
 * OneDrive received improvements.
 * UWP login screen has received a slight improvement.
 * XAML start menu is now displayed correctly.

Hidden features
The following hidden features have been found within this build:


 * Hidden lock screen - enabled by setting  to 1 under   in the registry like in build 9845.
 * Enable XAML Start menu - create and set  to 1 under
 * Search box on the taskbar - enabled by setting  to 1 under

Hidden apps
There are a few hidden apps in this build:


 * Windows Default Lock Screen - accessed by running
 * Cloud Experience Host - accessed by running
 * Windows Shell Experience Host - accessed by running

Window thumbnail border color error
If window auto-colorization is enabled, the window thumbnail borders on the taskbar do not change color even after the wallpaper changes. This issue can be remedied by manually changing the window color through the Control Panel or restarting Windows.

Updates
Only two updates were released for build 9879:
 * 6.4.9879.2.fbl_release_currentfr.141107-1950 - KB3016656 and KB3016725