@item @strong{Incompatible} configuration file format change: YAML is
replaced with Hjson, due to its simplicity, without noticeable lack
of either functionality or convenience.
+@strong{Incompatible} plain packet format changes. Older versions are
+ not supported. @code{zlib} compression is replaced with
+ @code{Zstandard}, due to its speed and efficiency, however library
+ version is not mature enough.
@item @command{nncp-cfgnew} generates configuration file with many
comments. @option{-nocomments} option can be used for an old
behaviour.