Also, ligatures ("ffi" -> "FFI"). Here's the 102 single Unicode points which, after upper(), map to more than one point:

  >>> for i in range(1_114_112):
  ...   s = chr(i)
  ...   if len(s) != len(s.upper()): print(i, s, s.upper())
  ...
  223 ß SS
  329 ʼn ʼN
  496 ǰ J̌
  912 ΐ Ϊ́
  944 ΰ Ϋ́
  1415 և ԵՒ
  7830 ẖ H̱
    ...
  8188 ῼ ΩΙ
  64256 ff FF
  64257 fi FI
    ...
  64279 ﬗ ՄԽ