add: var menulist = document.getElementById("defaultFont"); if (menulist.selectedIndex == -1) { menulist.insertItemAt(0, "", "", ""); menulist.selectedIndex = 0; } 
context:   init: function ()  {    this._pane = document.getElementById("paneContent");    this._rebuildFonts();  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/c7181c7870e294b654f5eff7b0623ebea0a403cb/content.js/buggy/browser/components/preferences/content.js