You know, I've always wondered why people substitute ß with ss if it's not available in the typeset. The name of ß is literally "Eszett", so it should be substituted with sz.
The german prononciation of the letter ß is eszett but the word weiß is pronounced Weiss. Even in German you will never see weiß written in weisz. Weiss is not technically accurate either but is shown that way from time to time
In the past sz was also used, but it's not allowed in modern spelling. The ß was (is?) used for both ss and sz, to the point where nobody knew anymore which it was originally.
