rem: var node = viewer.getSelectedNode(); if (!node) return false; 
add: var node = viewer.selectedNode; if (!node || node.nodeType != Node.ELEMENT_NODE) return false; 
context:   cmdInspectBrowserIsValid: function()  {    var node = viewer.getSelectedNode();    if (!node) return false;        var n = node.localName.toLowerCase();    return n == "tabbrowser" || n == "browser" || n == "iframe" || n == "frame" || n == "editor";  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/a7c48464e3280bcd1d3585d7cc0bc61c943ad5a5/dom.js/clean/extensions/inspector/resources/content/viewers/dom/dom.js