systemd-confext — This command is an alias of `systemd-sysext`. It follows the same principle as `systemd-sysext`, but

How to use the systemd-confext command: This command is an alias of systemd-sysext. It follows the same principle as systemd-sysext, but instead of working on /usr and /opt, confext will extend only /etc.

systemd-confext — This command is an alias of systemd-sysext. It follows the same principle as systemd-sysext, but instead of working on /usr and /opt, confext will extend only /etc.

View documentation for the original command:

tldr systemd-sysext

tldr-pages: linux/systemd-confext