Mariabackup's --help option disappeared

$ mariadb-backup --version

mariadb-backup based on MariaDB server 10.4.13-MariaDB debian-linux-gnu (x86_64)

$ mariadb-backup --help   

mariadb-backup based on MariaDB server 10.4.13-MariaDB debian-linux-gnu (x86_64)

Open source backup tool for InnoDB and XtraDB

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Usage: mariadb-backup [--defaults-file=#] [--backup | --prepare | --copy-back | --move-back] [OPTIONS]

Default options are read from the following files in the given order:

/etc/my.cnf /etc/mysql/my.cnf ~/.my.cnf 

The following groups are read: xtrabackup mariabackup mysqld server mysqld-10.4 mariadb mariadb-10.4 client-server galera

The following options may be given as the first argument:

--print-defaults          Print the program argument list and exit.

--no-defaults             Don't read default options from any option file.

The following specify which files/extra groups are read (specified before remaining options):

--defaults-file=#         Only read default options from the given file #.

--defaults-extra-file=#   Read this file after the global files are read.

--defaults-group-suffix=# Additionally read default groups with # appended as a suffix.

  -V, --verbose       display verbose output

  -v, --version       print xtrabackup version information

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$ mariadb-backup --version

mariadb-backup based on MariaDB server 10.5.4-MariaDB debian-linux-gnu (x86_64)

$ mariadb-backup --help

mariadb-backup: unknown option '--help'