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 ?
}
            this.linkService.eventBus?.dispatch("dispatcheventinsandbox", {
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              detail: {
                id,
                name: "Keystroke",
                value: elementData.beforeInputValue,
                change: event.data,
                willCommit: false,
                selStart,
                selEnd,
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            });
          });
        }
        this._setEventListeners(
          element,
          [
            ["focus", "Focus"],
            ["blur", "Blur"],
            ["mousedown", "Mouse Down"],
            ["mouseenter", "Mouse Enter"],
            ["mouseleave", "Mouse Exit"],
            ["mouseup", "Mouse Up"],
          ],
          event => event.target.value
        );
      }
      if (blurListener) {
        element.addEventListener("blur", blurListener);