Attach (recommended) or Link to PDF file here:
[0 NIF MODELO 30.pdf](https://github.com/mozilla/pdf.js/files/7187486/0.NIF.MODELO.30.2.pdf)

Configuration:
- Web browser and its version: firefox nightly
- Operating system and its version: linux debian

Steps to reproduce the problem:
1. Open the PDF
2. Click on the button  `Rellenar Formulario` (top right of the first page)
3. There is the pop-up "Stay... or Leave...`.

It's a bit annoying from the user pov and it doesn't make sense (nobody wants to leave the form but just reset it)

It works fine when replacing  `""` by `"#"` here:
https://github.com/mozilla/pdf.js/blob/7082ff9bf876b98fbda118cdbd6267d3c0df6948/src/display/annotation_layer.js#L483

@Snuffleupagus, you changed this few month ago:
https://github.com/mozilla/pdf.js/commit/e2b6d79dee9ffd2aba715d6b3cb8fa143d86153c

do you have some ideas ?
case AnnotationType.SQUARE:
        return new SquareAnnotationElement(parameters);
      case AnnotationType.CIRCLE:
        return new CircleAnnotationElement(parameters);
      case AnnotationType.POLYLINE:
        return new PolylineAnnotationElement(parameters);
      case AnnotationType.CARET:
        return new CaretAnnotationElement(parameters);
      case AnnotationType.INK:
        return new InkAnnotationElement(parameters);
      case AnnotationType.POLYGON:
        return new PolygonAnnotationElement(parameters);
      case AnnotationType.HIGHLIGHT:
        return new HighlightAnnotationElement(parameters);
      case AnnotationType.UNDERLINE:
        return new UnderlineAnnotationElement(parameters);
      case AnnotationType.SQUIGGLY:
        return new SquigglyAnnotationElement(parameters);
      case AnnotationType.STRIKEOUT:
        return new StrikeOutAnnotationElement(parameters);
      case AnnotationType.STAMP:
        return new StampAnnotationElement(parameters);
      case AnnotationType.FILEATTACHMENT:
        return new FileAttachmentAnnotationElement(parameters);
      default:
        return new AnnotationElement(parameters);
    }
  }
}
class AnnotationElement {