_onFabricMouseUp() {
    const canvas = this.getCanvas();

    this.fire(eventNames.OBJECT_ADDED, this._createLineEventObjectProperties());

    this._line = null;

    canvas.off({
      'mouse:move': this._listeners.mousemove,
      'mouse:up': this._listeners.mouseup,
    });
  }
Mouseup event handler in fabric canvas
@private