After the implementation of the missing QOpenGLFunction bindings, the example was able to run, but without the animation.

The following code needs to be commented to display the color pattern of the OpenGL under Qml example,
but uncommenting it does not allow the application to properly execute, getting a black screen and no animation.

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

There seems to be an event inside the SequentialAnimation that is blocking the progress of the application.