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Improving Defense Against Javascript Spam
By David King
  In recent weeks, Facebook has witnessed an increased volume of scams that involve malicious javascript, which sends spam from users accounts to their friends’ walls. In addition to the latest security updates, mainly involving Facebook's partnership with Web of Trust to deter malicious links on the site, Facebook is now educating users about how to protect their accounts when they first log on. Facebook is asking people to share the part of the help section that covers malicious script scams.
  While Facebook is trying to plug the holes in the site, which happens to be heavily reliant on javascript, the company is taking extra steps to educate users about the risks and how to identify such scripts. Some users who log in are now seeing the message below which suggests that the user shares one of Facebook’s help pages with other users.

These messages appear to be showing up mostly among those users who have fallen for the latest hacks. In addition to sharing the message about how to protect yourself, Facebook alerts the user that they have recently fallen for one of the attacks with a new message that appears when they next login.
In short, there is no dislike button!