PG18 protocol version

In the PG18 docs, I see:
https://www.postgresql.org/docs/18/protocol-message-formats.html

StartupMessage (F)
:
Int32(196608)

The protocol version number. The most significant 16 bits are the
major version number (3 for the protocol described here). The
least significant 16 bits are the minor version number (0 for the
protocol described here).

In my understanding PG18 will support protocol version 3.2, but above
statement claims that the protocol minor version is 0. Initially I
thought this is because libpq will use 3.0 unless max_protocol_version
is specified as a connection string. But in the BackendKeyData section
of the doc, it clearly explains v3.2 format. So I suspect this is just
a typo.

Best regards,
--
Tatsuo Ishii
SRA OSS K.K.
English: http://www.sraoss.co.jp/index_en/
Japanese:http://www.sraoss.co.jp