On the following page https://mariadb.com/kb/en/library/mariabackup-options 
the --apply-log-only option is missing.

For example, on this page:
https://mariadb.com/kb/en/library/incremental-backup-and-restore-with-mariabackup/#preparing-the-backup 
we can find a link to:
https://mariadb.com/kb/en/mariabackup-options/#-apply-log-only
which doesn't show the desired content as the option is not mentioned.

Thomas