The most tasteless joke I heard all week was, "Oh, the Japanese are used to radiation poisoning." I'm not certain it was meant as a joke. Anyway, it's wrong: Americans have a lot more experience with with radiation and radionuclide contamination than the Japanese. The difference is that we did it to ourselves. Or, depending on your viewpoint, the U.S. military-industrial complex did it to us. ("Americans", here, includes Canadians and Mexicans.) Estimates are that more than a million more Americans died horribly of cancer than would have without above-ground testing. The people responsible were never prosecuted.

Graydon informs me that the feature I needed in Firefox is implemented as an extension, "BarTab".