I have mac, typed this --- again --- and nothing? Layout says U.S.
edit: another comment gave a mac shortcut – — - <--- one of these might be it
Option-Shift-Hyphen.
Just --- only works when you have the text replacement thing on (the same thing that turns (C) into ©).
Option-Shift-Hyphen.
Just --- only works when you have the text replacement thing on (the same thing that turns (C) into ©).