Resized Qt Quick Canvas element corrupted with WebAssembly

import QtQuick 2.5

Rectangle {
    id: root

    Canvas {
        property var array: [[width/2,0], [width, height], [0, height]]
        property color color: "black"

        height: width
        width: parent.width/4
        anchors.centerIn: parent

        Timer {
            running: true
            interval: 3000
            onTriggered: parent.width = parent.width/2
        }        
        onArrayChanged: requestPaint()
        onColorChanged: requestPaint()
        onPaint: {
            var ctx = getContext('2d')
            ctx.save()
            ctx.clearRect(0, 0, width, height)
            ctx.fillStyle = color
            ctx.beginPath()
            ctx.moveTo(array[0][0], array[0][1])
            for (var i = 1; i < array.length; i++) {
                ctx.lineTo(array[i][0], array[i][1])
            }
            ctx.closePath()
            ctx.fill()
            ctx.restore()
        }
    }
}