When uploading a pdf file, I get Warning: Unimplemented widget field type "null", falling back to base field type at pdf.worker.js. The file is not loading.
I'm using the chrome browser. All other files are processed fine, but this one is not. Help solve the problem.
[usn2020.pdf](https://github.com/mozilla/pdf.js/files/5936611/usn2020.pdf)

maxY = Math.max(maxY, MY);
    }
    buffer.push("Q");
    const formDict = new Dict(xref);
    const appearanceStreamDict = new Dict(xref);
    appearanceStreamDict.set("Subtype", Name.get("Form"));
    const appearanceStream = new StringStream(buffer.join(" "));
    appearanceStream.dict = appearanceStreamDict;
    formDict.set("Fm0", appearanceStream);
    const gsDict = new Dict(xref);
    if (blendMode) {
      gsDict.set("BM", Name.get(blendMode));
    }
    const stateDict = new Dict(xref);
    stateDict.set("GS0", gsDict);
    const resources = new Dict(xref);
    resources.set("ExtGState", stateDict);
    resources.set("XObject", formDict);
    const appearanceDict = new Dict(xref);
    appearanceDict.set("Resources", resources);
    const bbox = (this.data.rect = [minX, minY, maxX, maxY]);
    appearanceDict.set("BBox", bbox);
    this.appearance = new StringStream("/GS0 gs /Fm0 Do");
    this.appearance.dict = appearanceDict;
    
    
    this._streams.push(this.appearance, appearanceStream);
  }
}
class WidgetAnnotation extends Annotation {