Implicit conversion from NSUrl? to Uri? crashes on null value

[J-Swift]

Steps to Reproduce

1. Create a Swift class that has a nullable URL property:

@objc(Foo)
public class Foo : NSObject {
    @objc
    public var imageUrl: URL?
    
    @objc
    public init(url: URL?)
    {
        self.imageUrl = url
        super.init()
    }
}

2. Generate bindings

[BaseType (typeof(NSObject))]
[DisableDefaultCtor]
interface Foo
{
    // @property (copy, nonatomic) NSURL * _Nullable imageUrl;
    [NullAllowed, Export ("imageUrl", ArgumentSemantic.Copy)]
    NSUrl ImageUrl { get; set; }

    // -(instancetype _Nonnull)initWithUrl:(NSURL * _Nullable)url __attribute__((objc_designated_initializer));
    [Export ("initWithUrl:")]
    [DesignatedInitializer]
    IntPtr Constructor ([NullAllowed] NSUrl url);
}

3. Try to convert to URI? implicitly

var foo = new Foo(null);
Uri? imageUri = foo.ImageUrl;

Expected Behavior

imageUri should be null since it is nullable

Actual Behavior

Crash:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Foundation.NSUrl.op_Implicit(NSUrl url)

I have to fake out the compiler to get it to work, otherwise the implicit conversion kicks in

Uri? uri;
if (foo.ImageUrl == null)
{
    uri = null;
}
else
{
    uri = foo.ImageUrl;
}

Environment

I'm running this on a Mac through dotnet CLI and VSCode since its a MAUI app

Build Logs

Example Project (If Possible)

[chamons]

Looks like our implicit operator should return null here.

[chamons]

I can reproduce this with:

			global::System.Uri uri = null;
			NSUrl sUrl = uri;