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):

"The reference does not point to a /Page dictionary."
            );
          }
          if (!node) {
            return null;
          }
          if (!isDict(node)) {
            throw new FormatError("Node must be a dictionary.");
          }
          parentRef = node.getRaw("Parent");
          return node.getAsync("Parent");
        })
        .then(function (parent) {
          if (!parent) {
            return null;
          }
          if (!isDict(parent)) {
            throw new FormatError("Parent must be a dictionary.");
          }
          return parent.getAsync("Kids");
        })
        .then(function (kids) {
          if (!kids) {
            return null;
          }
          const kidPromises = [];
          let found = false;
          for (let i = 0, ii = kids.length; i < ii; i++) {
            const kid = kids[i];
            if (!isRef(kid)) {