startIdIfNeeded(t = "") {
    let s = t;
    return t === kt && (this.startEndCount++, s = `${Pt}${this.startEndCount}`), s;
  }
If the id is a start node ( [*] ), then return a new id constructed from
the start node name and the current start node count.
else return the given id

@param {string} id
@returns {string} - the id (original or constructed)
@private