Note: The Safe Browsing feature in Firefox has been renamed to Phishing Protection, but it's still now as Safe Browsing internally.
= Overview History =
[http://www.google.com/tools/firefox/safebrowsing/ Google Safe Browsing] was an anti-phishing extension released by Google on [http://labs.google.com/ labs.google.com] in December 2005. Google has released this extension to the Mozilla Foundation under MPL 1.1/GPL 2.0/LGPL 2.1 in order that it might be used as part of Firefox if desired. We've landed this change on the trunk as a global extension as of 7 March 2006. The next steps are to figure out whether this is something we want to use as the base for an anti-phishing feature in Firefox. Of course, whether it is enabled or even shipped is still a matter for discussion, as is the final form the extension might take, its UI, the way users opt-in, and the like.
You can read the discussion that lead up to to its integration in https://bugzilla.mozilla.org/show_bug.cgi?id=329292