I created a pdf for https://github.com/mozilla/pdf.js/pull/14023:
[same_fields(1).pdf](https://github.com/mozilla/pdf.js/files/7168340/same_fields.1.pdf)
The 3 checkboxes have the same name (`Check Box2`) and have the same values (`Off` and `Yes`).
In pdf.js, these checkboxes behave like radio buttons in the same group (which is wrong) because of:
https://github.com/mozilla/pdf.js/commit/1fcffe80349a98378262c8a16f7b50ff34c3fe82
Since they've the same values they must be synced: if one is checked (resp. unchecked) then all others are checked (resp. unchecked).
if (pin) {
      this.pinned = true;
    }
    if (this.hideElement.hidden) {
      this.hideElement.hidden = false;
      this.container.style.zIndex += 1;
    }
  }
  /**
   * Hide the popup.
   *
   * @private
   * @param {boolean} unpin
   * @memberof PopupElement
   */
  _hide(unpin = true) {
    if (unpin) {
      this.pinned = false;
    }
    if (!this.hideElement.hidden && !this.pinned) {
      this.hideElement.hidden = true;
      this.container.style.zIndex -= 1;
    }
  }
}
class FreeTextAnnotationElement extends AnnotationElement {