Attach (recommended) or Link to PDF file here: [form-cms1500.pdf](https://github.com/mozilla/pdf.js/files/5670936/form-cms1500.pdf) (Original opened in Acrobat and checked one radio-button)
Original Source: https://www.cigna.com/static/www-cigna-com/docs/health-care-providers/form-cms1500.pdf

Configuration:
- Web browser and its version: FF 83.0
- Operating system and its version: Win 10 Pro
- PDF.js version: 2.7.355

Steps to reproduce the problem:
1. Open the PDF here: https://mozilla.github.io/pdf.js/web/viewer.html
2. See that all radio-buttons are checked, which is wrong.

What is the expected behavior? (add screenshot)
![grafik](https://user-images.githubusercontent.com/12390057/101734698-f72d3900-3ac0-11eb-817e-94ce276797e8.png)

What went wrong? (add screenshot)
![grafik](https://user-images.githubusercontent.com/12390057/101734712-fc8a8380-3ac0-11eb-833d-412243a7950c.png)

This radio-button field can be found in object `45 0 obj`.
selEnd: event.target.selectionEnd,
              },
            });
          }
          _blurListener(event);
        });
        element.addEventListener("mousedown", event => {
          elementData.beforeInputValue = event.target.value;
          elementData.beforeInputSelectionRange = null;
        });
        element.addEventListener("keyup", event => {
          
          if (event.target.selectionStart === event.target.selectionEnd) {
            elementData.beforeInputSelectionRange = null;
          }
        });
        element.addEventListener("select", event => {
          elementData.beforeInputSelectionRange = [
            event.target.selectionStart,
            event.target.selectionEnd,
          ];
        });
        if (this.data.actions?.Keystroke) {
          
          
          element.addEventListener("input", event => {
            let selStart = -1;
            let selEnd = -1;
            if (elementData.beforeInputSelectionRange) {
              [selStart, selEnd] = elementData.beforeInputSelectionRange;