rem: while (column_node) { 
add: while (column_node && menuitem) { 
context: function enable_sort_menuitems() {    var columns = document.getElementById('theColumns');    var column_node = columns.firstChild;    var head = document.getElementById('headRow');    var tree_column = head.firstChild;    var skip_column = document.getElementById('popupCell');    var menuitem = document.getElementById('fill_after_this_node');    menuitem = menuitem.nextSibling    while (column_node) {        if (skip_column != tree_column) {            if ("true" == column_node.getAttribute("hidden")) {                menuitem.setAttribute("disabled", "true");            } else {                menuitem.removeAttribute("disabled");            }        }        menuitem = menuitem.nextSibling;        tree_column = tree_column.nextSibling;        column_node = column_node.nextSibling;        if (column_node && column_node.tagName == "splitter")            column_node = column_node.nextSibling;    }}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/b6269a319650a05c78b29aef853096d70c7a6398/nsTreeUtils.js/buggy/xpfe/global/resources/content/nsTreeUtils.js