Attach (recommended) or Link to PDF file here:
See pdf in https://github.com/mozilla/pdf.js/issues/3109

Configuration:
- Web browser and its version: Firefox nightly
- Operating system and its version: Windows 10
- PDF.js version: builtin viewer

Steps to reproduce the problem:
1. Look at outlines

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/141514798-0e656865-1cbf-4fb8-a89b-530d36da23c9.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/141514740-c95e0237-8bf4-4129-a4a5-cb2ea5a3f4df.png)

assert(typeof str === "string", "Invalid argument for stringToBytes");
  const length = str.length;
  const bytes = new Uint8Array(length);
  for (let i = 0; i < length; ++i) {
    bytes[i] = str.charCodeAt(i) & 0xff;
  }
  return bytes;
}
/**
 * Gets length of the array (Array, Uint8Array, or string) in bytes.
 * @param {Array<any>|Uint8Array|string} arr
 * @returns {number}
 */
function arrayByteLength(arr) {
  if (arr.length !== undefined) {
    return arr.length;
  }
  assert(arr.byteLength !== undefined, "arrayByteLength - invalid argument.");
  return arr.byteLength;
}
/**
 * Combines array items (arrays) into single Uint8Array object.
 * @param {Array<Array<any>|Uint8Array|string>} arr - the array of the arrays
 *   (Array, Uint8Array, or string).
 * @returns {Uint8Array}
 */
function arraysToBytes(arr) {