Attach (recommended) or Link to PDF file here:
[Erstattung von Arbeitgeberaufwendungen nach __ 56 Abs. 1 und 57, 58 Infektionsschutzgesetz - Antrag(1).pdf](https://github.com/mozilla/pdf.js/files/6009589/Erstattung.von.Arbeitgeberaufwendungen.nach.__.56.Abs.1.und.57.58.Infektionsschutzgesetz.-.Antrag.1.pdf)

Also available at: [formularserver.bayern.de](https://formularserver.bayern.de/intelliform/forms/stmi+regierungen/rof/b5/55.2/rof_55.2-086/index)

Configuration:
- Web browser and its version: FF 85.0.2 and FF 86.0b9
- Operating system and its version: Win 10
- PDF.js version: 
FF 85.0.2:
const pdfjsVersion = '2.7.345';
const pdfjsBuild = 'b194c820b';

FF 86.0b9:
const pdfjsVersion = '2.7.510';
const pdfjsBuild = '631bada0d';

- Is a browser extension:
no
Steps to reproduce the problem:
1. load pdf document

What is the expected behavior? (add screenshot)
This is with latest Chrome:
![grafik](https://user-images.githubusercontent.com/584660/108499622-e2360880-72ae-11eb-82a7-b181619ff079.png)


What went wrong? (add screenshot)
The checkboxes for e.g. "Geschlecht" are black and you cannot see which one is checked. But this is true for every checkbox in that document.
![grafik](https://user-images.githubusercontent.com/584660/108499753-14e00100-72af-11eb-89d3-1f5ca652e058.png)

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

constructor(parameters) {
    super(parameters);
    this.data.annotationType = AnnotationType.POPUP;
    let parentItem = parameters.dict.get("Parent");
    if (!parentItem) {
      warn("Popup annotation has a missing or invalid parent annotation.");
      return;
    }
    const parentSubtype = parentItem.get("Subtype");
    this.data.parentType = isName(parentSubtype) ? parentSubtype.name : null;
    const rawParent = parameters.dict.getRaw("Parent");
    this.data.parentId = isRef(rawParent) ? rawParent.toString() : null;
    const parentRect = parentItem.getArray("Rect");
    if (Array.isArray(parentRect) && parentRect.length === 4) {
      this.data.parentRect = Util.normalizeRect(parentRect);
    } else {
      this.data.parentRect = [0, 0, 0, 0];
    }
    const rt = parentItem.get("RT");
    if (isName(rt, AnnotationReplyType.GROUP)) {
      
      
      parentItem = parentItem.get("IRT");
    }
    if (!parentItem.has("M")) {
      this.data.modificationDate = null;
    } else {
      this.setModificationDate(parentItem.get("M"));
      this.data.modificationDate = this.modificationDate;