Firefox snap.svg problem

Is snap.svg is really needed for bpmn.io ? If not, how to remove it? I have a problem when pick element from palette and drop it to canvas. This problem only occurred on firefox. After I check it out, the problem is at the part of snap.svg. It says “TypeError: point is undefined”, for more detailed :

SnapPoints.prototype.add = function(snapLocation, point) {

  var snapValues = this._snapValues[snapLocation];

  if (!snapValues) {
    snapValues = this._snapValues[snapLocation] = { x: [], y: [] };
  }

  if (snapValues.x.indexOf(point.x) === -1) {
    snapValues.x.push(point.x);
  }

  if (snapValues.y.indexOf(point.y) === -1) {
    snapValues.y.push(point.y);
  }
};

SOLVED, after update bpmn-modeler.js the problem just solved