@jospoortvliet @bert_hubert @niels @Karlitschek https://github.com/nextcloud/server/issues/25290 << digging here.
from: server/apps/lookup_server_connector/lib/UpdateLookupServer.php
/**
* check if we should update the lookup server, we only do it if
*
* + we have an internet connection
* + the lookup server update was not disabled by the admin
* + we have a valid lookup server URL
*
* @return bool
*/