WebView2 external dependency cannot be installed from an MSIX package on a Windows 10 target machine

Daniel1175 Bumping this thread, but providing more information...

I Deployed a package similar to as described, on Windows 11 23H2 and latest Appinstaller.  I also added Optional="false", in an attempt to determine if the dependency was being attempted.

The package was successfully installed by the DesktopAppInstaller, however the app didn't work because WebView2 was not working.

Finding #1:

After installing, running the Get-AppXLog cmdlet shows that the following warning occured during the installation:

App manifest validation warning: Declared namespace http://schemas.microsoft.com/appx/manifest/externaldependencies is inapplicable, it will be ignored during manifest processing. 

This would likely indicate that the dependency would be ignored since the namespace isn't being supported.  A check of the latest documentation (win32dependencies:ExternalDependency (Windows 10, Windows 11) - Windows UWP applications | Microsoft Learn) shows no listed minimum versions, although in the Requirements table it does say "virtualization" for the item column, but I believe that to be a typo.  The minimum version of AppInstaller is stated, but that is satisfied.

I also noticed that in the example, the MinVersion fields for the target OS were too high (11.0 and 12.0 don't exist, at least not yet), but as this is an example one assumes that a 10.0 number like 10.0.19041.0 should be fine if there is no explicit minimum version mentioned in the documentation.

Further confirmation by using Get-AppXPackage shows that no dependency package was added to the system when the package was installed.

Finding #2:

Furthermore, checking Winget, I can find no package with the Microsoft.WebView2 name.  The closest match might be Microsoft.EdgeWebView2Runtime. 

Finding #3:

Hoping that perhaps all that is needed I also tried a manual installation of the WebView runtime (exe downloader from the Microsoft website), but this too does not satisfy the needs of the package running in the container.

Summary

From this, I assume that either the entire documentation is incorrect, was never implemented, or a typo in the documentation regarding the namespace itself is the cause.  I can find no corrected namespace to try after looking under every rock I can find.

IT Pros remain at a standstill and are unable to package the growing number of vendor apps that use WebView2 in their products.