In the live version of VRChat, attaching an IKFollower component to the head transform avoids inheriting scale, and therefore makes the attached object visible in first-person view. This can be convenient when making HUDs.
In 876, this no longer appears to work; while there are potential workarounds using fixed joints, these are less efficient and break on worlds with the combat system enabled.
Repro avatar: avtr_c3234d5f-8a3d-4a2c-bbbb-5afe1316ffcf (private)