When I try to open the "manage scripts" window with greasemonkey or "manage styles" in stylish, the same thing happens.
I get a window that's been reduced to nothing but the title bar, and only long enough to fit the min/restore/max buttons. When I expand it, it says "page load error" in the title bar and gives me the following information.
Address not found
Firefox can't find the server at c.
The browser could not find the host server for the provided address.
* Did you make a mistake...
I think we all know the error page.
Quite frustrating. I can't modify, delete, or add user scripts or user styles.