Windows 10 build 20279

Windows 10 build 20279.1 is the twenty-fifth and final Insider Preview build of Iron, the 21H1 development semester of Windows as a service. This build was released on 14 December 2020 to all Insiders on the Dev Channel who opted to receive builds from the  branch as the last officially released from this cycle for desktop, since the next build moved all Dev Channel Insiders to receive builds from the Cobalt cycle. Builds after this one, however, exist on other platforms such as Windows 10X (later cancelled), its server counterpart Windows Server 2022, and as Docker layer images.

Bugs

 * The update process to this build has a chance of hanging for extended periods of time.
 * Live preview doesn't work for pinned site tabs on some machines.
 * Some users are seeing error 0x80070426 when using their Microsoft account to sign into various apps. Restarting usually fixes this.
 * The modern Disk Management page (Settings → System → Storage → Manage Disks and Volumes) in the Settings app is blank, as a result, it won't display any drives present. To workaround this issue, use the classic Disk Management tool to manage disk drives.