Attach (recommended) or Link to PDF file here:
https://www.nta.go.jp/taxes/tetsuzuki/shinsei/annai/joyaku/annai/pdf2/250.pdf

Configuration:
- Web browser and its version: Firefox 81.0a1
- Operating system and its version: Debian 5.6.7-1
- PDF.js version: latest in Firefox nightly
- Is a browser extension: No

Steps to reproduce the problem:
1. Open the pdf and paste the following text "本 店 又 は 主 た る 事 務 所 の 所 在 地" in "Full name" and in "Domicile and residence" textfields
2. Print or Save the pdf 

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/91207547-30f05480-e709-11ea-9abd-2af5d970dc46.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/91207663-69902e00-e709-11ea-8a1d-1ddd30cf0621.png)

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

expect(isArrayBuffer(new Uint8Array(0))).toEqual(true);
    });
    it("handles non-array buffer values", function () {
      expect(isArrayBuffer("true")).toEqual(false);
      expect(isArrayBuffer(1)).toEqual(false);
      expect(isArrayBuffer(null)).toEqual(false);
      expect(isArrayBuffer(undefined)).toEqual(false);
    });
  });
  describe("isBool", function () {
    it("handles boolean values", function () {
      expect(isBool(true)).toEqual(true);
      expect(isBool(false)).toEqual(true);
    });
    it("handles non-boolean values", function () {
      expect(isBool("true")).toEqual(false);
      expect(isBool("false")).toEqual(false);
      expect(isBool(1)).toEqual(false);
      expect(isBool(0)).toEqual(false);
      expect(isBool(null)).toEqual(false);
      expect(isBool(undefined)).toEqual(false);
    });
  });
  describe("isNum", function () {
    it("handles numeric values", function () {
      expect(isNum(1)).toEqual(true);
      expect(isNum(0)).toEqual(true);
      expect(isNum(-1)).toEqual(true);
      expect(isNum(1000000000000000000)).toEqual(true);
      expect(isNum(12.34)).toEqual(true);