I about that age 😉
I wonder if this is an American thing or perhaps "English" (as in language) thing. I was taught German in school and that language has it's very own grammatical braindances. For example we have der, die das for "the" but if I use das before a , it has one s. Were, if I use the same word right after a comma it has two S - dass. But I've never heard of "emdash". Thanks for sharing that with me.