Just noticed that multiple people type ¯\_(ツ)_/¯ but it ends up getting messed up as ¯_(ツ)_/¯ since \ is treated as a backslash. I imagine there might be others that may break as well. It would do well to have an optional extension to have a list of all the ASCII emoticons to avoid breaking it up.
¯\_(ツ)_/¯ --> ¯_(ツ)_/¯
()[0.o]() --> ()0.o
ツ isn’t ASCII, though. I don’t think it affects original Western sideways emoticons, because :-\ or :\ isn’t usually followed by anything but a space and I don’t think \-) means anything conventionally. So it’s just original Eastern 1-line multi-character emoji that predate the proprietary Japanese telco and recent Unicode encodings.
To do this we may need another spec to specific common emotions.
I think maybe some third-party extensions could finish this work, not commonmark.