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I've noticed for a very long time that when you try to copy a link location or open a link on Facebook, it modifies the link and passes it through l.php . For example, I can be sent to http://www.facebook.com/l.php?u=http%3A%2F%2Fwww.google.com%2F&h=DKVUritNDJDJLDLVbldoDLFKBLOD5dlfDJY_-d3fgDUaA9b even though my browser render the link preview as http://www.google.com/ . Today, I took a closer look using Firebug and found that Facebook puts onmousedown="UntrustedLink.bootstrap($(this)[...] in the <a> tag. The second I right clicked the link, I saw the href attribute change in Firebug. This worries me. The advice many of us have given to less tech-savvy people (check where the link is taking you before you click so that you don't become a victim of phishing) now seems to have become useless. Isn't this a security risk? Can't phishing websites misuse this? Why don't browsers prevent this behavior either by disallowing onmousedown to c