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)

constructor(parameters) {
    super(parameters);
    this.data.annotationType = AnnotationType.CIRCLE;
  }
}
class PolylineAnnotation extends MarkupAnnotation {
  constructor(parameters) {
    super(parameters);
    this.data.annotationType = AnnotationType.POLYLINE;
    this.data.vertices = [];
    
    
    
    const rawVertices = parameters.dict.getArray("Vertices");
    if (!Array.isArray(rawVertices)) {
      return;
    }
    for (let i = 0, ii = rawVertices.length; i < ii; i += 2) {
      this.data.vertices.push({
        x: rawVertices[i],
        y: rawVertices[i + 1],
      });
    }
  }
}
class PolygonAnnotation extends PolylineAnnotation {