Hi,
I have a playground to reproduce:
https://playground.babylonjs.com/indexstable#AVXVIQ
vs
https://playground.babylonjs.com/index.html#AVXVIQ
As you can see when you move the camera, the coloured progress bar does not stay parented to the camera as it did before. I don't believe this is intended.
If you switch to latest stable, however, then it does properly stay parented (although with different pivot matrix behaviour). My suspicion is it changed here (https://github.com/BabylonJS/Babylon.js/commit/07e15e49febe47e45f5d4958f722778b5f06d881).