IIRC UTF-8 proposal used to go to 6 bytes as they already felt that not having part of the code point in the first byte was an issue somehow. I think at least

IIRC UTF-8 proposal used to go to 6 bytes as they already felt that not having part of the code point in the first byte was an issue somehow. I think at least 7 should be allowed. 42 bits could contain all sorts of information. "UTF-8000" is still ANSI-safe and although it loses some of the properties such as a header code only appearing once in a byte sequence, it is perfectly viable to encode arbitrarily sized unsigned integers.