The new protocol dissector for X Protocol in MySQL was just merged to the master branch in Wireshark. To get it build Wireshark from the master branch or wait for the next release.
This protocol is using Google Protobuf, which makes it much easier to work with than the regular MySQL protocol.
See also: https://dev.mysql.com/doc/dev/mysql-server/latest/page_mysqlx_protocol.html
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