Template for C++ WinUI App generates D9047: option 'await' has been deprecated

[ChrisGuzak]

Describe the bug

I created a new WinUI C++ Packaged App and built it. this warning was emitted.

Should? be easy to switch to the conformant mode.

cl : command line  warning D9047: option 'await' has been deprecated and will be removed in a future release.
     Standard C++ coroutines are available by default in C++20 or later, or use '/await:strict' in earlier language modes.
cl : command line  warning D9047: option 'await' has been deprecated and will be removed in a future release.

Steps to reproduce the bug

• in VS, File New Project... WinUI C++ App Packaged
• F5 to build

observe the warning output

Expected behavior

no warnings!

To fix this, updating <LanguageStandard> to stdcpp20 resolves the warning.

NuGet package version

None

Packaging type

No response

Windows version

No response

IDE

No response

Additional context

No response

[lauren-ciha]

Thank you for your feedback! We've made the fix and it's shipping in the Visual Studio 18.1 servicing release (December 19, 2025).