"ShaderEffect: Property 'source' is not assigned a valid texture provider (std::nullptr_t)" when setting ColorOverlay's source to null

import QtQuick 2.7
import QtQuick.Controls 2.3
import QtGraphicalEffects 1.0

ApplicationWindow {
    id: main
    visible: true
    width: 640
    height: 480

    Rectangle {
        id: rect
        color: "grey"
        width: 128
        height: 128
        anchors.centerIn: parent
    }

    MouseArea {
        id: mouseArea
        anchors.fill: rect
        hoverEnabled: true
    }

    ColorOverlay {
        id: hoveredEntityMarkerColorOverlay
        anchors.fill: rect
        source: mouseArea.containsMouse ? rect : null
        color: mouseArea.containsMouse ? "red" : "green"
    }
}