I get error spam because AnimationPlayer couldn't detect a sky material. How to fix please?

Godot Version

4.3 stable

Question

This error occurs only when I change the scene not when the scene is run primarily. I investigated a bit, and it seems like the AnimationPlayer have problems detecting the sky_material/shader_parameters properties.

I don’t have this before Godot 4.3 but now I have it. Is this an engine bug?

Error:
E 0:00:16:0154 material_set_param: Parameter “material” is null.
<C++ Source> servers/rendering/renderer_rd/storage_rd/material_storage.cpp:2139 @ material_set_param()