The source code for the version of WinUI 3 in the WinAppSDK 1.7-experimental3 is available. 1.7-experimental3 is an experimental release for the WinAppSDK that includes bug fixes for earlier versions, access to non-stable APIs, and new features including new windowing controls, and support for c# developers to use the 'BadgeNotifications' API.

Check out our release notes for the list of fixed issues and new or experimental APIs in this release.

Download the NuGet package for 1.7-experimental3 here: https://www.nuget.org/packages/Microsoft.WindowsAppSDK/1.7.250127003-experimental3.