CoreWebView2WebMessageReceivedEventArgs.AdditionalObjects throws a Microsoft.CSharp.RuntimeBinder.RuntimeBinderException exception

[mikeduglas]

Description
An access to CoreWebView2WebMessageReceivedEventArgs.AdditionalObjects in WebMessageReceived event handler throws following exception:

[6980] WebMessageReceived: Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: the most suitable overloaded method for "System.Runtime.InteropServices.Marshal.GetObjectForIUnknown(System.IntPtr)" has several invalid arguments
[6980]    in CallSite.Target(Closure , CallSite , Type , Object ) 
[6980]    in System.Dynamic.UpdateDelegates.UpdateAndExecute2[T0,T1,TRet](CallSite site, T0 arg0, T1 arg1) 
[6980]    in CallSite.Target(Closure , CallSite , Type , Object ) 
[6980]    in Microsoft.Web.WebView2.Core.COMDotNetTypeConverter.CoreWebView2ObjectCollectionViewCOMToNet(ICoreWebView2ObjectCollectionView rawObjectCollection) 
[6980]    in Microsoft.Web.WebView2.Core.CoreWebView2WebMessageReceivedEventArgs.get_AdditionalObjects() 
[6980]    in claedge.ClaEdge.WebMessageReceived(Object sender, CoreWebView2WebMessageReceivedEventArgs e)

Version
SDK: 1.0.1774.30
Runtime: 113.0.1774.35
Framework: WinForms
OS: Win11

Repro Steps

• Create a webView.WebMessageReceived event handler.
• Use "FilesDropped" example from https://github.com/MicrosoftEdge/WebView2Feedback/blob/main/specs/WebMessageObjects.md
• Try to access CoreWebView2WebMessageReceivedEventArgs.AdditionalObjects property:
  var additionalObjects = e.AdditionalObjects;

Screenshots

Additional context

AB#44726780

[mikeduglas]

2 weeks - no reaction. "The following APIs have been promoted to Stable and are now included in this Release SDK." - does anyone ever test new features before reporting them as stable?
Reproducible in current runtime 113.0.1774.42.

[yildirimcagri-msft]

Hi, thanks for reporting this! Will look into this with high priority.

[yildirimcagri-msft]

I have a fix prepared for this. Unfortunately, some of our .NET tests (including the one that would have caught this) were not running properly in the pipeline; hence this is why this was overlooked. Apologize for inconvenience and will keep you updated on when this will be fixed (I'm pushing for an urgent SDK release for this). Thanks for your patience!

[yildirimcagri-msft]

Hi, wanted to update you that the fix for this has merged and has been bumped up to the next SDK release, which is anticipated to be next week.

[mikeduglas]

Thanks for the update.

[mikeduglas]

Nothing changed in the SDK 1.0.1823.32 and Runtime 114.0.1832.37: same Microsoft.CSharp.RuntimeBinder.RuntimeBinderException.
Please reopen as not fixed.

[yildirimcagri-msft]

Looking

[yildirimcagri-msft]

Hi @mikeduglas, we've looked into this and unfortunately turns out the fix wasn't properly cherry picked to the release SDK. Apologies for this again. The fix will be available in the prerelease SDK, which will be out on 6/12. You should be able to use the prerelease SDK without having to switch the runtime channel out of Stable as the fix is only at the SDK level.

[yildirimcagri-msft]

Hi again, I've verified with the latest prerelease package 1.0.1905, this issue is fixed. Closing this issue now.

[mikeduglas]

Yup, it works in 1.0.1905.