https://ftfy.vercel.app/?s=Pyrenee%C3%83%C2%ABn is broken and explains the wrong source text

[jpluimers]

I tried running https://ftfy.vercel.app/?s=Pyrenee%C3%83%C2%ABn to see what would cause Pyreneeën

In stead of explaining Pyreneeën, it explained Pyreneeën

A log of the difference between these two is at https://gist.github.com/jpluimers/adff0ffe6eec6fdc7eab642ffdfd4ee5

I tried archiving the current faulty behaviour at https://web.archive.org/web/20211107130727/https://ftfy.vercel.app/?s=Pyrenee%C3%83%C2%ABn (which failed with a server error 500) and https://archive.md/to6Vt (which succeeded)