color property on QtQuick Window doesn't work

The following link states "Setting this property is more efficient than using a separate Rectangle."

https://qt-project.org/doc/qt-5.1/qtquick/qml-qtquick-window2-window.html#color-prop

However you get the warning (and no window shown):

Warning: QQml_colorProvider: no color provider has been set!
QQmlApplicationEngine failed to load component
main.qml:13 Invalid property assignment: color expected

import QtQuick.Window 2.0

Window {

    title: "My Application"

    visible: true

    width: 200
    height: 100

    color: "black"
}

If I change to using an ApplicationWindow from QtQuick.Controls then it works fine.

import QtQuick.Controls 1.1

ApplicationWindow {

    title: "My Application"

    visible: true

    width: 200
    height: 100

    color: "black"
}