Like a good little geek, I upgraded to Firefox 1.0.3 when it was released. All was well except for links that used JavaScript to pop up a new window. They didn’t do anything but leave a hung firefox.exe process on my Windows machine (I didn’t check on Ubuntu Linux yet).
After some searching on the mozillaZine forums, I found this thread which mentioned that people running the User Agent Switcher extension had this problem and fixed it by uninstalling it. I did that on mine and sure enough, it works.
Thanks, mozillaZine forums! 
