Cannot detach window from its window container

I'm embedding a Qml Wayland compositor into a widget application using QWidget::createWindowContainer(), later i need to get rid of the container but i still need to keep the window around.
So i call window->setParent(nullptr) and delete the container.
The container will then delete the window. It should not, as per documentation:

The container takes over ownership of window. The window can be removed from the window container with a call to QWindow::setParent().

I've track down the crash, and it all boils down to ChildRemoved event not being sent to QWindowContainer. That is the only piece of code that nullify d->window.
https://code.woboq.org/qt5/qtbase/src/widgets/kernel/qwindowcontainer.cpp.html#298

As d->window is not null, the window gets deleted by QWindowContainer dtor.

My current work around is to manually send a madeup child removed event before deleting the window container.

It doesn't seem to be specific to wayland, any embedded Qml window will crash.

Example: just hack the Qml 'embeddedinwidgets' example:

    QWidget *container = QWidget::createWindowContainer(m_quickView);
    m_quickView->setParent(nullptr);
    delete container;
    container = QWidget::createWindowContainer(m_quickView);

And watch it crash, as `m_quickView` has just been deleted by `container`