OpenGL Content under SplitView

[madoodia]

Hello guys

based on This SplitView is a layout that will split contents and separate them with a draggable splitter

I used This to load OpenGL Content in QML

But something weird happened
and SplitView don't Split the 3D Contents in separated layout

Image: (as you can see OpenGL content is underneath all SplitView)

It should be placed in the left side of the SplitView
In the right side I have a transparent Rectangle

as you can see the Note Rectangle and Text are in right layout but the OpenGL is not

Code: main.qml

import QtQuick 2.13
import QtQuick.Controls 2.13

Item {
    id: main
    width: 720
    height: 600
    
    SplitView {
        id: splitView
        anchors.fill: parent

        handle: Rectangle {
            implicitWidth: 4
            implicitHeight: 4
            color: SplitHandle.pressed ? "#81e889"
                : (SplitHandle.hovered ? Qt.lighter("#c2f4c6", 1.1) : "#c2f4c6")
        }

        GL {
            implicitWidth: 250
        }
        
        Rectangle {
            implicitWidth: 350
            SplitView.minimumHeight: 250
            color: Qt.rgba(0.0, 1.0, 0.0, 0.1)
            Text {
                anchors.fill: parent
                wrapMode: Text.WordWrap
                text: "Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello Hello "
            }
        }
    }
}

GL type is another GL.qml

import QtQuick 2.13
import OpenGLUnderQML 1.0

Item {
    id: lView

    Squircle {
        anchors.fill: parent
        SequentialAnimation on t {
            NumberAnimation { to: 1; duration: 2500; easing.type: Easing.InQuad}
            NumberAnimation { to: 0; duration: 2500; easing.type: Easing.InQuad}
            loops: Animation.Infinite
            running: true
        }
    }

    Rectangle {
        color: Qt.rgba(1, 1, 1, 0.7)
        radius: 5
        border.width: 1
        border.color: "white"
        anchors.fill: label
        anchors.margins: -10
    }

    Text {
        id: label
        color: "black"
        wrapMode: Text.WordWrap
        text: "The background here is a squricle rendered with raw OpenGL using the 'beforeRender()' signal in QQuickWindow. This text label and its border is rendered using QML"
        anchors.right: parent.right
        anchors.left: parent.left
        anchors.bottom: parent.bottom
        anchors.margins: 20
    }
}

OpenGLUnderQML come from https://doc.qt.io/qt-5/qtquick-scenegraph-openglunderqml-example.html

and this is main.cpp

#include <QtQuick/QQuickView>
#include <QtWidgets/QApplication>
#include <QtCore/QUrl>
#include <QtQml/QtQml>

#include "squircle.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    qmlRegisterType<Squircle>("OpenGLUnderQML", 1, 0, "Squircle");

    QQuickView view;
    view.setResizeMode(QQuickView::SizeRootObjectToView);
    view.setSource(QUrl("qrc:/main.qml"));
    view.show();

    return app.exec();
}

I don't know it is related to the way OpenGL content is rendered? or it should be behave like an Item (like Rectangle) after registering?!

Would be appreciated for any help

thanks