Mac OS: QWidget::createWindowContainer loses focus and can't get it back

A Qml ListView placed into a QWidget via QWidget::createWindowContainer loses focus when the user deactivates application by switching to another one and focus does get restored when the user re-activates application by bringing it back to the front.

I've included a minimal example project to demonstrate this issue. Run the project. Click in the window. Press the up/down arrow keys to move the highlighted item. Now Cmd-Tab to another application such as Finder. Then Cmd-Tab back. Click in the window again and try the arrow keys. They no longer work (no focus).

You can also use qmlscene to run the raw xyz.qml. In this case, everything works properly, as expected.