VRChat SDK - Avatars Ver.3.8.0
Sorry if there are any mistakes because I used machine translation.
There appears to be a configuration error in the animator controller of the Avatars SDK sample.
In the default FX layer, within the vrc_AvatarV3FaceLayer, in the Eyes layer, the Empty state does not have an animation clip assigned. Therefore, this state behaves the same as when Write Defaults is turned on. If the FX layer is built in its original sample state, bugs from Write Defaults being on fortunately do not occur. However, if you use the sample as a base and then make modifications to the FX layer by adding elements afterward, bugs may potentially occur.
Similarly, the Empty state in the Idle layer of vrc_AvatarV3IdleLayer, which is stored in the same directory as vrc_AvatarV3FaceLayer, also does not have an animation clip assigned. Fortunately, since the Idle layer is set to Additive, no bugs occur, but this is still an unhealthy state that should be fixed.