binlog_row_metadata is incorrectly documented as a session variable

https://mariadb.com/kb/en/replication-and-binary-log-system-variables/#binlog_row_metadata

binlog_row_metadata
Description: Controls the format used for binlog metadata logging.
NO_LOG: No metadata is logged (default).
MINIMAL: Only metadata required by a replica is logged.
FULL: All metadata is logged.
Commandline: --binlog-row-metadata=value
Scope: Global, Session
Dynamic: Yes

but in fact

MariaDB [test]> set binlog_row_metadata = no_log;

ERROR 1229 (HY000): Variable 'binlog_row_metadata' is a GLOBAL variable and should be set with SET GLOBAL