Operating system: windows 10 64 bit
Graphics card: RTX 2060 super
Broken: Blender 2.90 official / but it happen since a while now with older blender version
Worked: reported once here : https://developer.blender.org/T76381
Short description of error
Blender doesn't save animation keyframe input (color/Value ...) in shader node with luxcore render engine.
From the blendluxcore Devs it is a blender issue.
Exact steps for others to reproduce the error
1/ install luxcore render engine from here : https://luxcorerender.org/download/
2/ in blender switch to Luxcore engine
3/ add a shader matte (or any shader)
4/ animate any shader value of your choice.