That's great and works on Safari and FF at least. Amended jQuery block.

// <![CDATA[
$(document).ready(function() {
  $("*").bind("click",
              function(evt){
                  var info = $(this).position();
                  info["height"] = $(this).height();
                  info["width"] = $(this).width();
                  info["lineage"] = $(this).parents()
                             .map(function () {
                                   return this.tagName;
                                  })
                             .get().reverse().join(" > ");

                  $.ajax({url:"/cgi/position.pl"
                         ,data:info
                         ,dataType:"json"
                         ,type:"POST"
                         ,success: function(data){
                            $("#tag").append(data.status + " ")
                          }
                        });

                  evt.cancelBubble = true; // NEW!
                  if (evt.stopPropagation) evt.stopPropagation();
              });
});
// ]]>
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