Managed Debugging Assistant CallbackOnCollectedDelegate after dialog gets closed

[chucker]

I'm calling the lib as follows:

var d = new MyTaskDialog();
var result = d.ShowModal(this);

MyTaskDialog has a custom button (style CommandLinks), a default icon, and a title. (This appears to also happen with an even simpler dialog.)

After clicking the button, the Managed Debugging Assistant CallbackOnCollectedDelegate throws. As I understand it, this is roughly a use-after-free error:

The callbackOnCollectedDelegate managed debugging assistant (MDA) is activated if a delegate is marshaled from managed to unmanaged code as a function pointer and a callback is placed on that function pointer after the delegate has been garbage collected.

As I understand it, the Show() method in TaskDialog cleans up hr too early.