Using QRhiWidget with a Vulkan backend on macOS

I'm trying to use the new QRhiWidget with a Vulkan backend on macOS.
We want to integrate our existing Vulkan code into an existing Qt project. The idea is to force a Vulkan backend for the QRhiWidget in combination with QRhiCommandBuffer::ExternalContent.

My first step is to get the Simple RHI Widget example running on my machine:

• I installed the Vulkan SDK which includes MoltenVK
• I compiled Qt 6.7.1 myself to enable Vulkan support in Qt (somewhere in the configure output it mentions “Vulkan ...... Yes”)
• As QRhiWidget uses Metal as the default backend on macOS, I added following line to the example code to ensure Vulkan is used (added to the constructor of ExampleRhiWidget):

 setApi(QRhiWidget::Api::Vulkan);

• I set the QT_VULKAN_LIB environment variable to the location where libMoltenVK.dylib is located

After these steps, I was hoping to successfully run the example application. However, the application hangs on startup.
It seems that for some reason in src/plugins/platforms/cocoa/qnsview_drawing.mm, the displayLayer() function is constantly being called without returning to the qt event loop in between. I suspect this explains why the application hangs...

When using Metal or OpenGL in the setAPI statement, the example runs fine.
Next to that I tried to run the Hello Vulkan Cubes example to make sure my Vulkan/MoltenVK setup is working properly. This example (which isn't using QRhiWidget) is working fine.

So I suspect something in QRhi(Widget) is broken when used in combination with Vulkan on macOS.