I was trying to use GUI.Image to start an HUD (like video games) into my virtual visit, but when I used GUI.Image, when I wanted to triggered the element, it looks like a bug.
Here is a playground : https://www.babylonjs-playground.com/#XCPP9Y#3175
So for the onPointerClickObservable, it is not working at all.
For onPointerDownClickObservable, the first click is working, but to click another time, the pointer has to get out of the canvas of babylonJS. If I do that, there is no problem, but I guess this is not how the function was designed.
Hope you will figure it out.
Have a nice day,