<target
  class="PageTrackerTarget"
  name="back-button"
  path="global/back-button.tn0.xml"
><![CDATA[
PageTrackerTarget
"back-button"
{}
{ /ClientPage {
    CurrentEvent /ClientData get begin 
      PageCount 0 eq PageNumber 0 eq or
    end {deactivate} {activate} ifelse 
  } def
  /ClientUp { /back-page PileDict ContentsPileID get /Win get send } def
  /ItemPath {rr} def }
]]></target>

