"Han Unification" - in Unicode many Japanese characters are represented as Chinese characters that look different (and subjectively ugly). The Unicode consortium's answer is that you're supposed to use a different font or something when displaying Japanese, which is pretty unsatisfying (e.g. if you want to have a block of text that contains both Japanese and Chinese, you can't represent that as just a Unicode string, it has to be some kind of rope of segments with their own fonts, at which point frankly you might as well just go back to bytes-with-encoding which at least breaks very clearly and visibly if you get it wrong).