Like most people, I started with searching my own conditions, but I was surprised that I couldn't find them. Something like Klippel-Feil syndrome/deformity isn't normally rare enough not to make the list. I also couldn't find it by the more generic description "congenital fusion of cervical vertebrae" or variants on those terms.

Having a whole list of conditions starting from the beginning of the alphabet show up as soon as I click the search box isn't terribly useful. Waiting for me to get at least 2 or 3 characters in would be less distracting and more helpful.