So, I do have to say, the latest slew of spambots is at least funny, in a childish way.
There is, but you need the necessary permissions to be able to do so and they are normally set to administrator level by default, so we don't have the power to ban by IP. In fact, the only means that we have to ban spammers is through the spam clean up tool. I've removed at least ten accounts using that method this morning. I will add though that banning by IP is not necessarily that effective. First, it can catch genuine users in the IP ban and second if spammers are using rotating IPs it's neither use nor ornament.
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