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In IE9 on Win7, I can't seem to get to any test page. I can see jsperf.com and start to browse the test cases, but any link I click to open a specific test case gets into a redirect loop and breaks IE with the error "We were unable to return you to jsperf.com."
Consistently reproducible for me for any test case I attempt to look at, either from /browse, finding a page via Google, or pasting a URL directly.
Checkout this FAQ entry and see if it helps.