The Tor Browser / file revision

 <?xml version="1.0"?>

 <window class="reftest-wait" onload="changeKeys()"

         xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">

 <menuitem id="m1" label="Menu1" key="keyone"/>

 <menuitem id="m2" label="Menu2" key="keytwo"/>

 <menuitem id="m3" label="Menu3"/>

 <menuitem id="m4" label="Menu4"/>

 <menuitem id="m5" label="Menu5"/>

 <menuitem id="m6" label="Menu6" key="keythree" acceltext="Text"/>

 <menuitem id="m7" label="Menu7" key="keythree" acceltext="Text"/>

 <menuitem id="m8" label="Menu8" key="keythree" acceltext="Text"/>

 <menuitem id="m9" label="Menu9" key="keytwo"/>

 <script>

 function changeKeys()

 {

   document.getElementById("m1").setAttribute("key", "keytwo");

   document.getElementById("m2").removeAttribute("key");

   document.getElementById("m3").setAttribute("key", "keythree");

   document.getElementById("m4").setAttribute("key", "keyone");

   document.getElementById("m4").setAttribute("acceltext", "Text");

   document.getElementById("m5").setAttribute("acceltext", "Text");

   document.getElementById("m5").setAttribute("key", "keytwo");

   document.getElementById("m6").removeAttribute("key");

   document.getElementById("m7").removeAttribute("acceltext");

   document.getElementById("m8").removeAttribute("key");

   document.getElementById("m8").removeAttribute("acceltext");

   document.getElementById("m9").removeAttribute("key");

   document.documentElement.className='';

 }

 </script>

 <keyset>

   <key id="keyone" key="Z" modifiers="control"/>

   <key id="keytwo" key="Y" modifiers="control"/>

   <key id="keythree" key="X" modifiers="accel"/>

 </keyset>

 </window>