Let me hijack this post as I’ve encountered another issue and this is originally my playground I know more about.
As long as the 2nd camera for the advancedTexture of the GUI in the top left is present (as in not disposed), you can’t see nor use the gizmos activated from the inspector. Once disposed everything is working as expected, except if you want to turn the currently active gizmo off again, then you get a TypeError. If you want to rerun the scene you’ll then have to refresh the page, otherwise you’ll get another TypeError regarding the scene. (The refresh probably resets the clicked gizmos so that’s why it fixes).
When I tried adding 3D Buttons to my scene they weren’t visible at all untill the 2nd camera was disposed. Now I’m using Button Meshes (which work better for my use case anyway). These are visible but can’t be interacted with as long as the 2nd camera exists. I had a similar picking issue with my pickable cubes, but that was fixed by setting the correct camera for pointers
scene.cameraToUseForPointers = camera;. Sadly this doesn’t seem to affect the 3D Buttons.
The 2nd camera is only used because of the default render pipeline otherwise affecting the 2D GUI (as stated in the docs). If there is another way to disregard the pipelines effects for the gui I’ll gladly use that, instead of the hassle of a 2nd camera.
Take a look: https://playground.babylonjs.com/#59FFHD#89