i had some that wouldn't go away. turns out the path has to be "/" sometimes.
it's best to sweep through all keys with and without the path, nulling them all out.
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(2013/10/31) IE7:0.5, IE8:8.6, IE9:5.3, IE10:12.3, FF:17.7, CH:41.8, SF:8.1, MOBILE:20.4