Unicode Characters Rendering Issues

import QtQuick 2.10
import QtQuick.Window 2.10

Window {
    visible: true
    width: 1920
    height: 1080
    title: qsTr("Test Unicode Characters")

    FontLoader {
        id:sourceHanSancSCFontLoader
        source: "file:///opt/fonts/SourceHanSansSC-Light.otf"
    }

    function allCharacters() {
        var string = "";
        for(var i=19968;i<25343;++i) {
            string += String.fromCharCode(i)
        }
        return string
    }

    Text {
        text: allCharacters()
        anchors.centerIn: parent
        font.family: sourceHanSancSCFontLoader.name
        font.pointSize: 12
        font.weight: Font.Normal
        wrapMode: Text.Wrap
        color: "black"
        width: parent.width
        height: parent.height
    }
}