CUSTOM MATERIAL - Cannot add uniform after UBO created

Questions
1

In a previous version of Babylon.js I could assign a custom material to a submaterial but now when I do that i get “Cannot add an uniform after UBO has been created” error. Has anyone encountered this? Is there a workaround? @nasimiasl maybe you are familiar with this

2

Here is a playground to demonstrate https://www.babylonjs-playground.com/#1FPM0C#7

3

I’ve noticed that this one does not produce any webGL errors https://www.babylonjs-playground.com/#JUKXQD#186