facebook just started this today and gmail has been doing this for a while
Your user agent is corrupted by Fast Browser Search (FBSMTWB) and that identifies you as Firefox/3.6.10
see your user agent:
Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:184.108.40.206) Gecko/20100914 AskTbBLT/220.127.116.1104 Firefox/3.6.10 GTB7.1 (.NET CLR 3.5.30729) FBSMTWB
you must reset user agent
see also the next page about Fast Browser Search (FBSMTWB in the user agent).
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