Merge pull request #1049 from MicrosoftDocs/master

Merge master to live.

Author: craigloewen-msft

WSL/release-notes.md

@@ -10,6 +10,14 @@ ms.localizationpriority: high
 
 # Release Notes for Windows Subsystem for Linux
 
+## Build 21286
+For general Windows information on build 21286 visit the [Windows blog](https://blogs.windows.com/windows-insider/2021/01/06/announcing-windows-10-insider-preview-build-21286/).
+
+* Added a boot.command option to /etc/wsl.conf to enable start up commands.
+* Introduce wsl.exe --cd command to set current working directory of a command.
+* Improve mapping of NTSTATUS to Linux error codes. [GH 6063]
+* Improve wsl.exe --mount error reporting.
+
 ## Build 20226
 For general Windows information on build 20226 visit the [Windows blog](https://blogs.windows.com/windows-insider/2020/09/10/announcing-windows-10-insider-preview-build-20226/).