We have an overlay sprite that we fade-in/fade-out whenever we change levels. This is just a simple interpolation of the alpha color and set it unto the sprite. This overlay is implemented as a non destroyable object that persists. What happens is that somehow a combined mesh ("Combined Mesh (root:scene)") is assigned to the MeshFilter of the sprite when the next level is loaded. So whatever color assigned to it no longer changes the color of the sprite.
I don't want this happening. How do I prevent it? It happens automatically.