add:  toolbar.setAttribute('previousset', toolbar.currentSet);  
context: function wrapToolbarItems(){  for (var i = 0; i < gToolbox.childNodes.length; ++i) {    var toolbar = getToolbarAt(i);    if (isCustomizableToolbar(toolbar)) {      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: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/8395/73d69b6a8953514bd06da8a56ee32923c40ccf00/customizeToolbar.js/buggy/mail/base/content/customizeToolbar.js