I saw what you did there.
The "Nothing else: no lists, tables, links, quotes, images or rules" is from the docs indicating that these things are not supported.
En dash is the width of an “n”. Em dash is the width of an “M”, so a little wider.
Yeah, it’s somewhat a typography-nerdy thing :–) (gosh that looks terrible probably; edit: actually it’s surprisingly fine)
> indicating that these things are not supported
Of course, but it does sound a bit unnatural IMO. Then again, I’m going by the vibes here.