Image scaling produces an artifact around translucent areas

import QtQuick
import QtQuick.Controls

ApplicationWindow {
    id: appwindow
    width: 640
    height: 480
    visible: true
    color: "white"

    ToolButton {
        icon.source: "img.png"
        icon.color: "transparent"

        // works when not scaled:
        // icon.width: 96
        // icon.height: 96

        scale: 4
        anchors.centerIn: parent
    }
}