This is due to use of
enumValueIndex
in
VRCSDK\Dependencies\VRChat\Editor\Components3\VRCAvatarDescriptorEditor3AnimLayerGui.cs
The net result of this is, the layers are off by 1 between Inspector and Debug. And if you reset to default, your layers will be offset:
Debug and Normal inspectors show layers in different order
The immediate cause is the
VRCAvatarDescriptor.AnimLayerType
enum value for
SpecialIK
was removed. The order remained the same, and the values remained the same, but anything uses the "enum index" will break, including the VRCSDK3 VRCAvatarDescriptor Inspector.