The emoticon selector now requires 3 characters to open, so you can send emoticons such as :D directly.
in Steam Friends and Chat Changelog, 2019-04-17.
That would be a good idea... if it would actually count characters of the emoticon itself, not the whole message. People also like to append the classic ASCII cancer-free smiles to the end.
Nothing extracted yet.
In the chat window, typing colon (:) opens a menu with emoji suggestions. That would be great, only if typing another character (:D) and pressing enter afterwards (to send my message) wouldn't insert the entry I have my mouse cursor above.
The same happens on Windows.