Hi @Indranil Doe
Thank you for the reply and the hints.
FYI: As this is developed using react, we needed a way to add and remove event listener, we finally used a useCallBack hook to always point to the original event handler.
All works fine now.
But! we also want to move the zoom port/area left and right as you would on the normal zooming but it get stuck. You can see on your example as well if you zoom, and try to move the zoomed area left and right it does nothing.
Can you give pointers to this.