Service Discovery: Cannot register to a browsable gateway

If a gateway supports service discovery on itself and lists itself... the "register" button stays disabled by Gajim.

In src/disco.py this seems intentional (to not allow registration on the item being browsed). The comment there indicates this has to do with not wanting users to register new JIDs with servers via the service discovery dialog. However, just because something is browsable does not mean it's a server. Could not the service discovery identity category (which in this case is clearly gateway) be used to help with this?