I love this app and it really helps me write! Over the past couple months I have noticed that typing two hyphens (--) doesn't convert to em-dash if there is any text ahead of it. Sometimes I'll write the sentences and decide an em dash looks better than a comma, and when I change it, it just stays as --. It is a very minor inconvenience so I just correct it when I copy it to my main doc, but I figured I would let you know!