I'm not aware of Invisiclues ever having been "installed." I'm only familiar with them as booklets with "invisible" ink. And, at least initially, they were created at least quasi-independently of Infocom by someone who later joined Infocom.
The re releases I played they were under "hint" or "hints" or "help" or something.
There was an are you sure / really sure admonishment, then breadcrumb bit by bit hints towards solution.
They amused me for a time at 9-10, then later at maybe 14-15 or so I got into them again playing on a Palm VIIx with a folding Stowaway keyboard. I also read through HHGTTG on that same device.
https://archive.org/details/sci-fi-collection-the-usa/ and the like.