Configuring S3 Object Storage as Primary Storage: Error


I want to use an existing, pre-created and empty AWS S3 Bucket to be integrated as primary storage.

My config.php before finishing initial installation (installation wizard) looks like this:

$CONFIG = array (
  'htaccess.RewriteBase' => '/',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'apps_paths' => 
  array (
    0 => 
    array (
      'path' => '/var/www/html/apps',
      'url' => '/apps',
      'writable' => false,
    1 => 
    array (
      'path' => '/var/www/html/custom_apps',
      'url' => '/custom_apps',
      'writable' => true,
  'instanceid' => 'ocaeodq8o7rp',
  'objectstore' => 
  array (
    'class' => '\\OC\\Files\\ObjectStore\\S3',
    'arguments' => 
    array (
      'bucket' => 'nyendo-nextcloud',
      'autocreate' => false,
      'key' => 'XXX',
      'secret' => 'XXX',
      'use_ssl' => true,

After trying to finish the setup, I get an internal server error. The server logs tell the following:

"message":{"Exception": ... Creation of bucket \"nyendo-nextcloud\" failed. Error executing \"CreateBucket\" on \"\"; AWS HTTP error: Client error: PUT https:/ / resulted in a 409 Conflict response: ... <Error><Code>BucketAlreadyOwnedByYou</Code><Message> ... BucketAlreadyOwnedByYou (client): Your previous request to create the named bucket succeeded and you already own it. ...

I assumed that the config field 'autocreate' => false, should prevent nextcloud from creating a bucket. Correct?

Still Nextcloud fails to finish the setup because it apparently fails to create the S3 bucket which it is supposed to just use. Did I do something wrong with the configuration?

No ideas? I’m just wondering if this can be considered as a bug …
(Antworten gerne auch auf deutsch)