This is a bug that Facebook introduced to their Facebook Connect Javascript code on Wednesday. We've been tracking it since, and originally had a message at the top of the forums alerting users to the problem. We've removed it as Facebook has since pushed out a platform update to the Javascript (completely on their end), which they say should resolve the remaining issues for any users. It's sporadic who's experiencing this now, and unfortunately, we're at the hands of Facebook now to finalize the fix.
If you'd like to look at the official bug report (which we've posted our experiences into as well), see below:
bugs.developers.facebook.net/show_bug.cgi?id=14971
In short, be patient and the issue should fix itself. You can try clearing your cache and restarting your browser, which may help propagate the change sooner to you.
Sorry for the inconvenience!
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