Image layer.effect doesn't work with an effect over it

import QtQuick 2.11
import QtQuick.Window 2.11
import QtGraphicalEffects 1.0

Window {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")
    color: "green"
    Image{
        id: img1
        anchors.top: parent.top
        source: "https://doc.qt.io/style/theqtcompany.png"
        fillMode: Image.PreserveAspectFit
        visible: true
        layer.enabled: true
        layer.smooth: true
        layer.effect: ColorOverlay
        {
            color: "blue"
        }
    }
    FastBlur
    {
        anchors.fill: img1
        source: img1
        radius: 32
    }
    Image{
        id: img2
        anchors.bottom: parent.bottom
        source: "https://doc.qt.io/style/theqtcompany.png"
        fillMode: Image.PreserveAspectFit
        visible: false
    }
    FastBlur
    {
        anchors.fill: img2
        source: colov
        radius: 32
    }
    ColorOverlay
    {
        id: colov
        anchors.fill: img2
        color: "blue"
        source: img2
    }

}