ame.contentDocument;
                ['s1', 's2', 's3'].forEach(function(id){
                    const target = innerDocument.getElementById(id);
                    eventList.forEach(function(eventName) {
                        on_event(target, eventName, checkPointerEventCoordinates);
                    });

                    on_event(target, "click", function (event) {
                      if (!(event.target.id in clickedTargetList)) {
                          clickedTargetList.push(event.target.i