How can one install/update to a beta application? [Solved]

I would like to try deck 0.5.1-beta1 “available” on https://apps.nextcloud.com/ but I didn’t find any documentation on how to do this. So I simply decided to download the tar archive, and replaced the directory /apps/deck with the content of archive, changed the owner. Was this the correct way to do it, or was there anything else to do? Because when I did it, and logged in to nextcloud, I got the login page repeating the message “Waiting for cron to finish (checks again in 5 seconds) …” and the server went into the maintenance mode.

I got it. It sufficed to disable the application, stop httpd ( I am not sure if this is relevant), replace the directory, restart httpd, connect to nextcloud and enable the application again.