ComVariantMarshaller and ComVariant does not work well with Com interfaces

[m-celikba]

Description

Consider this example:

[GeneratedComInterface, Guid(..)]
interface IComItf
{
    ...
}

[GeneratedComClass, Guid(..)]
class ManagedComItf : IComItf
{
    ...
}

then:

IComItf instNative = CreateNativeImplementation();
IComItf instManaged = new ManagedComItf();

var v1 = ComVariantMarshaller.ConvertToUnmanaged(instManaged); // works
var v2 = ComVariantMarshaller.ConvertToUnmanaged(instNative); // <--------------- does not work

because of this passing a com interface to a com method as object fails when the method has this signature:
void Method([MarshalUsing(typeof(ComVariantMarshaller))] object obj);

Additionally these are missing:

var v3 = ComVariant.Create(instNative);
var instManaged2 = v1.As<IComItf>();

PS:
this works but does not help:
var v4 = ComVariantMarshaller.ConvertToUnmanaged(new UnknownWrapper(instNative)); // works

Reproduction Steps

see description

Expected behavior

ComVariantMarshaller should be able to work directly with COM interfaces

Actual behavior

ComVariantMarshallers cannot be created from COM interfaces

Regression?

No response

Known Workarounds

No response

Configuration

.NET9

Other information

No response

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