Cannot load QtQuickViewContent after QtQuickView is attached to view hierarchy

See Archive.zip for example project, based on the qtquickview_kotlin example.

Steps:

1. Create a QtQuickView instance and add it to the view hierarchy (LayoutGroup.addView(...))
2. After the view hierarchy has been loaded and rendered, call QtQuickView::loadContent() on the view added in step 1.
   • In the example project, this is done via button press.

Result:

Nothing happens, Qt libs are loaded in the background and the Qt main thread starts spinning, but the QML view is not shown.

Desired result:

The QtQuickViewContent gets loaded.