The → nc-who ← script can shows all logins and supports MySQL/MariaDB and PostgreSQL database backends.
Simply run nc-who monitor and select [ 2 ] to list all logins.
Example screen:
root@box:~# nc-who monitor
This script looks up for logged in users on your Nextcloud in "/var/www/nextcloud"
it updates at an adjustable refresh rate and lists ordered by last activity
press [1] for cookie based logins, [2] for all, [q] to quit
h.t.h.
ernolf