Missing Icon.highlightKey despite shown on docs

[Hunterk1241]

On the documentation, it tells you that you can change the default highlight key from DPadUp to any binding you seem fit. However, this seems to not be true as setting Icon.highlightKey does nothing. For example, doing Icon.highlightKey = Enum.KeyCode.ButtonY doesn't change it to ButtonY and keeps it as DPadUp. Perhaps a mistake?