rem: window.frames["accountCentralPane"].location = "about:blank"; 
add: window.frames["accountCentralPane"].location.href = "about:blank"; 
context: function HideAccountCentral(){    try    {        window.frames["accountCentralPane"].location = "about:blank";        document.getElementById("accountCentralBox").collapsed = true;        GetThreadTree().collapsed = false;        gSearchBox.collapsed = false;        var threadPaneSplitter = document.getElementById("threadpane-splitter");        threadPaneSplitter.collapsed = false;        if (!threadPaneSplitter.hidden && threadPaneSplitter.getAttribute("state") != "collapsed")            GetMessagePane().collapsed = false;        gAccountCentralLoaded = false;    }    catch (ex)    {        dump("Error hiding AccountCentral page -> " + ex + "\n");        return;    }}
meta: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/cddca7b1217f1f1a10c371a975c199b3efbaa9cc/mailWindow.js/clean/mailnews/base/resources/content/mailWindow.js