> How is that wrong? Not sure where, how or if it's defined as part of Unicode, but so far I assumed that for a Unicode grapheme there exists a notion of what the visual representation should look like. If Unicode still defines capital of ß as SS that's an error in Unicode due to slow adaption of the changes in the German language.

ẞ is not the preferred capital version, it is an acceptable variant (according to the Council for German Orthography).

I see, wasn't clear to me on what level you were asking. The letter ß has never been generally equivalent to ss in the German language.

From a user experience perspective though it might be beneficial to pretend that "ß" == "ss" holds when parsing user input.