bug completed
The short link code tex.se seems to work but TeX.SE does not. Likewise dba.se works but dba.SE does not.

These short link codes should be completely case insensitive.
Top Answer
Jack Douglas
shortlinks are all now case-insensitive.
SE site short links should be case insensitive.
Also, since TeX is to be written as TeX in text where the kerned and lowered version doesn't display, I'd like mixed-case versions to also link correctly (maybe only for specific versions, no general lower-casing, don't know which makes more sense and which is harder to implement)
As I'm pretty used to shorten `tex.stackexchange.com` to TeX.SX (and that was/is quite common for users of TeX.SX) I'd like to add that maybe also the .sx endings should work.