The Tor Browser / file revision

 <?xml version="1.0"?>

 <?xml-stylesheet href="chrome://global/skin/" type="text/css"?>

 <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" onload="var tree = document.getElementById('tree'), treeitem = document.getElementById('treeitem'); tree.parentNode.insertBefore(treeitem, tree);">

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     <treecol id="name" label="Name" primary="true" flex="1"/>

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     <treeitem id="treeitem">

       <treerow>

         <treecell label="Click the button below to crash"/>

       </treerow>

     </treeitem>

   </treechildren>

 </tree>

 </window>