The source code for the version of WinUI 3 in the WinAppSDK 1.8-experimental4 is available. 1.8-experimental4 is an experimental release for the WinAppSDK that includes bug fixes for earlier versions, access to non-stable APIs.

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

Download the NuGet package for 1.8-experimental4 here: https://www.nuget.org/packages/Microsoft.WindowsAppSDK/1.8.250702007-experimental14