The message and whois screens now scroll with your browser, so that if you're looking at a user account or message way down the list you don't have to scroll up to see them.
The close button also scrolls with your browser for all screens that have it.
You will probably need to hit the refresh button in your browser for these changes to show.
Let me know if any of these changes cause problems, or if there are other screens that should behave similarly.