Hi Charles,
To answer that question needs us to understand what you mean by "supported" :)
MySQL can use the utf8mb4 character set which has symbols for very nearly every written language on the planet (including a whole lot of emojis)
When symbols of one language are "rewritten" into two or more symbols from another language, that is called "transcoding" and it's a side effect of blending different character sets in your clients with the character set being used by the server to store the data.
Ensure that your entire toolchain (from user input to column definition) are all using the same character set. That's the best way to avoid this type of problem.
This topic is covered in excellent detail in several places on the web. Here is one I particularly like:
http://kunststube.net/encoding/
Yours,
--
Shawn Green
MySQL Senior Principal Technical Support Engineer
Oracle USA, Inc. - Integrated Cloud Applications & Platform Services
Office: Blountville, TN
Become certified in MySQL! Visit
https://www.mysql.com/certification/ for details.