This is a website issue, not firmware, so I didn't want to put it in the Bugs section. I'm using FF 3.6.12, XPsp3, and the login popup from Wikidot comes up and works, but when it goes back to TomatoUSB.org, its not logged in (and starting a new forum post asks for anonymous info). If I then go to Wikidot.com, it does show I'm logged in. No difference using Firefox in Safe Mode (as in "firefox.exe -safe-mode") btw.
In IE8, it works fine. New forum posts shows my default Wikidot info. I searched here and Wikidot for a similar issue, and didn't find anything.