Since #12241 we have notifications for this when the user navigates away from the viewer, but we do not yet warn when switching documents, which means that if you call e.g. `PDFViewerApplication.open` with a new document (or directly call `BaseViewer.setDocument` when using the viewer components standalone) there won't be any warning about losing form data. This should be addressed.
const hash = evt.hash;
  if (!hash) {
    return;
  }
  if (!PDFViewerApplication.isInitialViewSet) {
    PDFViewerApplication.initialBookmark = hash;
  } else if (!PDFViewerApplication.pdfHistory.popStateInProgress) {
    PDFViewerApplication.pdfLinkService.setHash(hash);
  }
}
let webViewerFileInputChange, webViewerOpenFile;
if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
  webViewerFileInputChange = function (evt) {
    if (PDFViewerApplication.pdfViewer?.isInPresentationMode) {
      return; 
    }