I used babylon.js gltf exporter for 3Ds Max 2020 and 2018 and i get this error for both versions. I uploaded the same files this week in sandbox and they worked just fine. This issue appeared today.
Hmm, this one is weird. I’ve been updating the KHR_materials_variants loader extension a lot and @Deltakosh has been adding functionality to the inspector, but I don’t repro this problem. Are you still seeing it?
This is wierd. Yesterday when i had the issue i asked a friend to test the model on his computer and it worked just fine for him. I uploaded again the models today and everything works just fine .