In reply to Make ejabberd pick up changes in external roster:
I got a tip to use add_rosteritem and delete_rosteritem in the HTTP API. I tested and they seem to be somewhat usable: if add_rosteritem is called for a currently connected user, that user is notified of the new roster item. However I have two problems:
Our web service has a bit complex method for building the roster. It's no problem to generate a complete list of roster items, but to find what roster items have been removed and added is not trivial. So I would much prefer a solution where Ejabberd could be notified that the (...)
In reply to To Reduce the gap between more than one user registration from one device:
Yes, search for the option registration_timeout in https://docs.ejabberd.im/admin/configuration/
Quite simply, in ejabberd.yml set: registration_timeout: infinity
Remember to remove that option after you finished registering accounts, or disable mod_register, so that spammers find difficult to abuse your server.