Windows 10X build 21319
| Build of Windows 10X | |
 | |
| OS family | Windows 10 (NT 10.0) |
|---|---|
| Version number | 10.0 |
| Build number | 21319 |
| Build revision | 1000 |
| Architecture | ARM64 |
| Build lab | rs_prerelease |
| Product type | |
| ModernPC | |
Windows 10X build 21319 is the only known build of Windows 10X from the Cobalt semester, unlike the public Manganese and Iron preview builds. A picture of the build being installed via Windows Update was posted to the BetaWiki Discord server on 25 September 2021.