SpinBox indicators stay hovered after being pressed and moving the mouse away

import QtQuick 2.5
import QtQuick.Controls 2.0

ApplicationWindow {
    visible: true
    width: 640
    height: 480

    SpinBox {
        id: mySpinBox
        from: 0
        to: 100
        value: 32
        up.indicator: Rectangle {
            id: upIndicator
            x: parent.width - width
            y: (parent.height - height) / 2
            implicitHeight: 40
            implicitWidth: 40
            color: mySpinBox.up.pressed ? "red" : (mySpinBox.up.hovered ? "blue" : "grey")
        }
    }
}