rem:  toolbar.setAttribute('previousset', toolbar.currentSet); 
add: if (aStorePreviousSet) toolbar.setAttribute('previousset', toolbar.currentSet); 
context: function wrapToolbarItems(){  for (var i = 0; i < gToolbox.childNodes.length; ++i) {    var toolbar = getToolbarAt(i);    if (isCustomizableToolbar(toolbar)) {      // save off the current set for each toolbar in case the user hits cancel      toolbar.setAttribute('previousset', toolbar.currentSet);      for (var k = 0; k < toolbar.childNodes.length; ++k) {        var item = toolbar.childNodes[k];        if (isToolbarItem(item)) {          var nextSibling = item.nextSibling;                    var wrapper = wrapToolbarItem(item);               if (nextSibling)            toolbar.insertBefore(wrapper, nextSibling);          else            toolbar.appendChild(wrapper);        }      }    }  }}
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/d311fe8c6f68546bc14903ce4c8aef7fff7b16a2/customizeToolbar.js/buggy/mail/base/content/customizeToolbar.js