Macromedia News Firefox Extension and Firefox 1.5
As Christian mentioned, Firefox 1.5 was released today. Unfortunately, it seems to have broken the Macromedia News Firefox extension.
Basically, if you click a link in the extension, it will prompt you to pick an app to handle the URL, and will then crash Firefox.
I am going to look into this, but it might take some time to isolate and / or work around the issue.