My FireFox is looking really really ugly since upgrading to 4.0 (definitely not how it's supposed to be looking), see screenshot below.
I had FF 4 RC installed earlier (which looked exactly the same, but I thought it was because it is a release candidate).
Un- and reinstalling firefox did not do the trick, I also tried disabling all add-ons. There is not other theme than the default (4.0) theme installed.
I know that deleting all Firefox stuff from "Documents and Settings" would probably help, but I would rather keep my firefox configuration/preferences etc, so if anyone can give me a clue what I can do about it, I would be very happy.