Word file used: 
[Formular_T.docx](https://github.com/mozilla/pdf.js/files/6907859/Formular_T.docx)

PDFs generated:
PDF 1: [Formular_T_default.pdf](https://github.com/mozilla/pdf.js/files/6907771/Formular_T_default.pdf)
PDF 2: [Formular_T_changed.pdf](https://github.com/mozilla/pdf.js/files/6907772/Formular_T_changed.pdf)

- PDF.js version: v2.9.359

Steps to reproduce the problem:
1. Create Word Document with Checkbox and check it.
2. Convert Word document to PDF using **Aspose.pdf** (for .net)

3. Extra: Change value of second Checkbox  in PDF 1 and save the file (PDF 2). The new File will show both Checkboxes checked in other browser, but only the newly checked one in PDF.js

Expected:
Checkbox is checked (pdf viewer from adobe/Chrome Version 92.0.4515.107 64-bit)
![image](https://user-images.githubusercontent.com/76941221/127659557-42be1cca-3c90-49b8-b224-70ee85aa1b30.png)

Result:
Checkbox is not checked (Mozilla Firefox/PDF.js)
![image](https://user-images.githubusercontent.com/76941221/127660064-e3cdc3f9-6887-4ae7-af27-d46cded69029.png)



return null;
    }
    value = value.trim();
    if (value === "") {
      
      return "";
    }
    let lineCount = -1;
    if (this.data.multiLine) {
      lineCount = value.split(/\r\n|\r|\n/).length;
    }
    const defaultPadding = 2;
    const hPadding = defaultPadding;
    const totalHeight = this.data.rect[3] - this.data.rect[1];
    const totalWidth = this.data.rect[2] - this.data.rect[0];
    if (!this._defaultAppearance) {
      
      
      
      
      
      this.data.defaultAppearanceData = parseDefaultAppearance(
        (this._defaultAppearance = "/Helvetica 0 Tf 0 g")
      );
    }
    const [defaultAppearance, fontSize] = this._computeFontSize(
      totalHeight,
      lineCount
    );