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 ?
const subtype = parameters.data.annotationType;
    switch (subtype) {
      case AnnotationType.LINK:
        return new LinkAnnotationElement(parameters);
      case AnnotationType.TEXT:
        return new TextAnnotationElement(parameters);
      case AnnotationType.WIDGET:
        const fieldType = parameters.data.fieldType;
        switch (fieldType) {
          case "Tx":
            return new TextWidgetAnnotationElement(parameters);
          case "Btn":
            if (parameters.data.radioButton) {
              return new RadioButtonWidgetAnnotationElement(parameters);
            } else if (parameters.data.checkBox) {
              return new CheckboxWidgetAnnotationElement(parameters);
            }
            return new PushButtonWidgetAnnotationElement(parameters);
          case "Ch":
            return new ChoiceWidgetAnnotationElement(parameters);
        }
        return new WidgetAnnotationElement(parameters);
      case AnnotationType.POPUP:
        return new PopupAnnotationElement(parameters);
      case AnnotationType.FREETEXT:
        return new FreeTextAnnotationElement(parameters);
      case AnnotationType.LINE:
        return new LineAnnotationElement(parameters);