Attach (recommended) or Link to PDF file here:  [test.pdf](https://akmer.aikucun.com/a94a8fe5ccb19ba61c4c0873d391e987982fbbd3_1616477914120_83.pdf)


Configuration:
- Web browser and its version: chrome 87.0.4280.88
- Operating system and its version: windows10
- PDF.js version: 2.6.347
- Is a browser extension:

Steps to reproduce the problem:
1. just open 

What is the expected behavior? (add screenshot)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/17724610/112087066-473f8f80-8bc8-11eb-8efb-56139ec42a9c.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

i.parent.items.push(outlineItem);
      obj = outlineDict.getRaw("First");
      if (isRef(obj) && !processed.has(obj)) {
        queue.push({ obj, parent: outlineItem });
        processed.put(obj);
      }
      obj = outlineDict.getRaw("Next");
      if (isRef(obj) && !processed.has(obj)) {
        queue.push({ obj, parent: i.parent });
        processed.put(obj);
      }
    }
    return root.items.length > 0 ? root.items : null;
  }
  get permissions() {
    let permissions = null;
    try {
      permissions = this._readPermissions();
    } catch (ex) {
      if (ex instanceof MissingDataException) {
        throw ex;
      }
      warn("Unable to read permissions.");
    }
    return shadow(this, "permissions", permissions);
  }
  /**
   * @private
   */
  _readPermissions() {