Ban email domains?

[Rho Delta]

Is there a way to ban email domains? Even with custom img captcha a few are getting through again. Is there a way to ban all .ru domains from registering? Everyone in my niche is American, I do not want anyone without an American email address registering.

 

[SyTry]

Hello, maybe this one :

[OzzModz] Email Whitelist

Simple addon that will allow you to specify allowed email clients. Users will only be able to use the email clients you specify in the addon options. When a user enters a email client that is not whitelisted, they get an error message...

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