For reference:
https://github.com/mozilla/pdf.js/issues/15571#issuecomment-1278141781
const id = this.getNextId();
    const editor = this.#createNewEditor({
      parent: this,
      id,
      x: event.offsetX,
      y: event.offsetY,
    });
    if (editor) {
      this.add(editor);
    }
    return editor;
  }
  /**
   * Set the last selected editor.
   * @param {AnnotationEditor} editor
   */
  setSelected(editor) {