readBox(node, objectStack) {
    /** @type {Array<number>} */
    const flatCoordinates = pushParseAndPop(
      [null],
      this.BOX_PARSERS_,
      node,
      objectStack,
      this,
    );
    return createOrUpdate(
      flatCoordinates[1][0],
      flatCoordinates[1][1],
      flatCoordinates[1][3],
      flatCoordinates[1][4],
    );
  }
@param {Element} node Node.
@param {Array<*>} objectStack Object stack.
@return {import("../extent.js").Extent|undefined} Envelope.