"Command "encryption:enable-master-key" is not defined"

Nextcloud version: 13.0.4
Operating system and version: Ubuntu 18.04
Web-server Version: Caddyserver
PHP version: 7.2

The issue you are facing:
I’ve just set up this new instance of Nextcloud. Now I want to enable master-keys for encryption, because I plan on using OnlyOffice which otherwise wont work with encryption.

But when I use the occ Command occ encryption:enable-master-key I get the following Error:
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Steps to replicate it:

  1. Set up a new instance of Nextcloud
  2. Setup Onlyoffice Document Server with docker
  3. try to enable masterkey
  4. ???
  5. Profit

The output of your Nextcloud log in Admin > Logging:
Nothing, even on lowest debug level

The output of your config.php file in /path/to/nextcloud (removed any identifiable info!):

<?php
$CONFIG = array (
  'instanceid' => '§id',
  'passwordsalt' => '$pwsalt',
  'secret' => '$sec',
  'trusted_domains' => 
  array (
    0 => '$ncurl',
  ),
  'datadirectory' => '/mnt/hidrive/users/gzd2u9qd5u95wo47z23kygjpptawdfit3qc9xtic',
  'overwrite.cli.url' => '$ncurl',
  'dbtype' => 'pgsql',
  'version' => '13.0.4.0',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'nextcloud',
  'dbpassword' => '$dbpw',
  'installed' => true,
  'memcache.local' => '\\OC\\Memcache\\Redis',
  'redis' => 
  array (
    'host' => 'localhost',
    'port' => 6379,
  ),
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'mail_smtpmode' => 'smtp',
  'mail_smtpauthtype' => 'PLAIN',
  'mail_smtpsecure' => 'tls',
  'mail_from_address' => 'nextcloud',
  'mail_domain' => '$mydomain',
  'mail_smtpauth' => 1,
  'mail_smtpport' => '587',
  'mail_smtpname' => '$mymail',
  'mail_smtppassword' => '$mypw',
  'mail_smtphost' => 'smtp.mailgun.org',
  'maintenance' => false,
);