havingBaseSizing() {
    var e;
    switch (this.style.id) {
      case 4:
      case 5:
        e = 3;
        break;
      case 6:
      case 7:
        e = 1;
        break;
      default:
        e = 6;
    }
    return this.extend({
      style: this.style.text(),
      size: e
    });
  }
Remove the effect of sizing changes such as \Huge.
Keep the effect of the current style, such as \scriptstyle.