docs: function eventMove ( event, data ) {
  
              // Fix #498
              // Check value of .buttons in 'start' to work around a bug in IE10 mobile (data.buttonsProperty).
              // https://connect.microsoft.com/IE/feedback/details/927005/mobile-ie10-windows-phone-buttons-property-of-pointermove-event-always-zero
              // IE9 has .buttons and .which zero on mousemove.
              // Firefox breaks the spec MDN defines.
              if ( navigator.appVersion.indexOf("MSIE 9") === -1 && event.buttons === 0 && data.buttonsProperty !== 0 ) {
                  return eventEnd(event, data);
              }
  
              // Check if we are moving up or down
              var movement = (options.dir ? -1 : 1) * (event.calcPoint - data.startCalcPoint);
  
              // Convert the movement into a percentage of the slider width/height
              var proposal = (movement * 100) / data.baseSize;
  
              moveHandles(movement > 0, proposal, data.locations, data.handleNumbers);
          }