billboardMode on a gltf assets doesn't works as it should

[Vinc3r]

For those interested, here the trick: https://www.babylonjs-playground.com/#WC7IJG#6

I’m still doubtful about the fact that a mesh set as a billboard doesn’t act as a billboard, IMO it have to act as this no matter its situation At least this restriction have to be mentionned in the doc & API.