Check out the event lot page in the ACP (under advanced). The user's deletion event should have been logged, and the IP address should have been saved.
... as long as your NodeBB is new enough, that is 🙂
Heh, wouldn't it be fun if we had a crowdsourced spammer database just for NodeBB forums... spam on one, get banned from every one in existence 😆 ...
@pichalite I am still confused that. it need update after install. But our node_module files always in ignore... so I don't thinks it's a good way to put plugs into node_module....