anchor.diff:          { assertion = ((acfg.adminpass != null || acfg.adminpassFile != null)
               && !(acfg.adminpass != null && acfg.adminpassFile != null));
             message = "Please specify exactly one of adminpass or adminpassFile";
  +        }
  +        { assertion = versionOlder cfg.package.version "21" -> cfg.config.defaultPhoneRegion == null;
  +          message = "The `defaultPhoneRegion'-setting is only supported for Nextcloud >=21!";
           }
         ];
   
  
positive.code:               'dbtype' => '${c.dbtype}',
                'trusted_domains' => ${writePhpArrary ([ cfg.hostName ] ++ c.extraTrustedDomains)},
                'trusted_proxies' => ${writePhpArrary (c.trustedProxies)},
              ];
            '';
            occInstallCmd = let
  
negative.code:           may be served via HTTPS.
          '';
        };
  
        defaultPhoneRegion = mkOption {
          default = null;
          type = types.nullOr types.str;
          example = "DE";
          description = ''
            <warning>
             <para>This option exists since Nextcloud 21! If older versions are used,
              this will throw an eval-error!</para>
            </warning>
  
            <link xlink:href="https://www.iso.org/iso-3166-country-codes.html">ISO 3611-1</link>
            country codes for automatic phone-number detection without a country code.
  
            With e.g. <literal>DE</literal> set, the <literal>+49</literal> can be omitted for
            phone-numbers.
          '';
        };
      };
  
      caching = {
  