Windows 10 build 9807

Windows 10 build 9807 is a pre-Technical Preview build of Windows 10, which was uploaded to the BetaWiki Discord server on 17 May 2022 only in the Simplified Chinese language and under the x86 architecture. This build was originally released to Microsoft partners participating in the Ecosystem Engineering Access Program (EEAP), as indicated by the  branch.

It is the first build to update the kernel version to 6.4, and the last build to refer to itself as Windows 8.1.

A PDF file detailing release notes as a part of the EEAP release of this build was posted several minutes after the build itself, identifying two previous EEAP releases. The SDK for this build identifies as the "Windows Software Development Kit for Windows 8.2" per this document.

Aero changes
The Aero theme's window borders have been made thinner, though the Aero Lite theme still has the thicker border style.

Windowed Metro
Native support for windowed Metro apps is now enabled by default. The title bar of them also received its own style.

New icons
Some icons (including Explorer's) have been changed to a flatter style.

Task View
A multi-desktop mode has been introduced.