I don't remember if I already put this in a more relevant place, but https://commons.wikimedia.org/wiki/User_talk:Elitre#Your_VFC_installation_method_is_deprecated is imho a good example of communication about a broken script. It redirects to more info about the issue, but also says what it is that needs to be done /and/ provides a direct way to enable the replacement gadget. (I am not sure if that code is actually a good idea or anything, but it looks effective.)
