Second, browsers could offer tools that resemble ad blockers or spam blacklists that would allow non-expert users to avoid connections to illegitimate sites that seem to have been validated.

第二，浏览器可以提供允许非专业使用者避免连接到似乎已批准的非法站点的类似广告阻拦者们或者垃圾邮件黑名单的工具。

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Last month's attack appears to be part of a fierce feud between organizations that monitor spam and try to block it and companies that accuse spam blockers of unjustly blacklisting them.

CNN: Spain arrests suspect in massive cyberattack