As Firefox 3 beta 1 has just been released, I have updated Server Spy to support the new version. Server Spy 0.1.3 is available from addons.mozilla.org, as usual.

BTW, Firefox 3 behaves quite nicely on my Mac. The UI still has to be polished, but the new rendering infrastructure is promising: very good-looking text, native widgets on Mac, ACID2 compliance... The only thing I'm missing is Sage-the-RSS-reader. It does not support Firefox 3 currently, and bumping maxversion to 3 doesn't do the trick. Indeed, as Sage heavily relies on bookmarks APIs that have been superseded by Places, a significant amount of work will be needed to adapt it.