Describe the bug
When attempting to re-configure a pubsub node, converse.js downloads the current configuration, merges the new configuration into the existing one, then re-submits the configuration.

When downloading and parsing the existing configuration, the parser removes the pubsub# prefix from the field names. This prefix does not get re-added when submitting the new configuration resulting in the new configuration being ignored by the server.

Tested with Openfire