Not smooth breathing and acute, but Unicode has two codepoints for acute accents (sort of). One is the modern Greek tonos, which often looks just like an acute

Not smooth breathing and acute, but Unicode has two codepoints for acute accents (sort of). One is the modern Greek tonos, which often looks just like an acute accent but sometimes appears as a dot or straight vertical line, and the other codepoint is the ancient Greek oxia (the ancient term for the acute accent), which appears with all the other marks and their combinations (grave, circumflex, smooth/rough breathing, iota subscript). Personally I type Greek using a vim keymap file, usually when writing LaTeX. I believe my keymap file is influenced by those older non-Unicode fonts, because I type w for ω and ;h for ή and >~h| for ᾖ. But my fellow students would mostly use Word. I don't know how they would type the letters, but commonly they would mix the tonos letters with everything else. I think what was happening is that Word would automatically substitute fonts that offered those codepoints, so it would end up showing Times for the letters with tonos and Palatino for the others (or something like that). Hence the ransom note effect.