Windows 10 build 21387 (co_release)
| Build of Cobalt | |
 | |
| OS family | Windows 11 (NT 10.0) |
|---|---|
| Version number | 10.0 |
| Build number | 21387 |
| Build revision | 1 |
| Architecture | x86, x64, ARM64 |
| Build lab | co_release |
| Compiled on | 2021-05-18 |
| Expiration date | |
| Timebomb | 2021-10-31 (+166 days) |
| SKUs | |
| Home (China, N, Single Language) Cloud (N) Pro (China Only, N, Single Language) Pro Education (N) Pro (N) for Workstations Education (N) Enterprise (N, (N) Evaluation, G (N)) Enterprise multi-session IoT Enterprise Team | |
| About dialog | |
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Windows 10 build 21387 (co_release) is the nineteenth Insider Preview build of Cobalt, the 21H2 development semester of Windows as a service. This build was released on 21 May 2021 to all Windows Insiders on the Dev Channel.
Changes[edit | edit source]
- Internet Explorer 11's functionality has been disabled and attempting to run its executable file (
iexplore.exe) will open Edge instead. It is still possible to run Internet Explorer ifieframe.dllis replaced with a copy from an older build. - The "Eco mode" experimental Task Manager feature introduced in build 21364 has been removed.
- The first logon animation has been updated to use the Segoe UI Variable typeface.
Bugs[edit | edit source]
News and interests[edit | edit source]
- The flyout might occasionally flash in the screen's top left corner when opened.
Camera Settings[edit | edit source]
- The Camera app does not respect the brightness adjustments made to a camera under its respective page.
Installation[edit | edit source]
- The update process to this build has a chance of hanging for extended periods of time.
- Some devices might fail to upgrade to this build with error code
0xc1900101due to a second issue different from that in build 21382.
OOBE[edit | edit source]
- The OOBE may use an incorrect font when this build is ran under Simplified Chinese language pack.
General[edit | edit source]
- Certain parts of Search, including the File Explorer search box, are not displaying correctly in the dark theme.
- The icons for Microsoft Edge and File Explorer in the taskbar are swapped in clean installations.
Gallery[edit | edit source]
Boot screen
First logon animation
