The FermatsLibrary page contains a pdf showing a photocopy of the original piece with some annotations at the side. The pdf is just a graphic and does not have highlightable text but the annotations are proper text.
Perhaps you have some minimal view enabled on your browser and are only seeing the annotations, the only "text" on the page.
Exactly! What's funny is that rather than simply failing hard it
silently kinda half-works, presenting me with a mashed-up, incoherent
mess that sort of reads like it might be a legit article, but written
by crazy person.
A good object lesson in an awful idea for web presentation in my
opinion, but amusing nonetheless.
Perhaps you have some minimal view enabled on your browser and are only seeing the annotations, the only "text" on the page.