rem: if (pref.value) 
add: if (pref.valueFromPreferences) 
context:   updateClearNowButtonLabel: function ()  {    var pref = document.getElementById("privacy.sanitize.promptOnSanitize");    var clearNowButton = document.getElementById("clearDataNow");    if (pref.value)      clearNowButton.label = clearNowButton.getAttribute("label1"); // "Clear Now..."    else      clearNowButton.label = clearNowButton.getAttribute("label2"); // "Clear Now"  },
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/e67e432a30a9414f6f119ce18aa2c3575183101a/privacy.js/buggy/browser/components/preferences/privacy.js