For those who are interested, that one is Alt-7 (numeric keypad) on Windows. This works because in the "OEM" codepage (e.g. 437), char 7 corresponds to a symbol that is mapped into Unicode to • (← I just typed this using Alt-7, and the arrow using Alt-27). In a similar way I type the infamous ones—the ones that give you away as an LLM even if you aren't one. It's Alt-0151, this time with no OEM codepage conversion because of the zero in front (anyway that codepage had no em-dashes, the closest one would be Alt-196, which is ─, i.e. a line drawing character).