STR:
  - Go to https://mozilla.github.io/pdf.js/web/viewer.html
  - Click on "Open File" and open a pdf

The `Download` button and the `Current view` one just disappear.
I can reproduce this bug with Firefox nightly, Chrome stable and Epiphany on debian.
throw new Error("Not implemented: createL10n");
  }
  static createScripting(options) {
    throw new Error("Not implemented: createScripting");
  }
  static get supportsIntegratedFind() {
    return shadow(this, "supportsIntegratedFind", false);
  }
  static get supportsDocumentFonts() {
    return shadow(this, "supportsDocumentFonts", true);
  }
  static get supportedMouseWheelZoomModifierKeys() {
    return shadow(this, "supportedMouseWheelZoomModifierKeys", {
      ctrlKey: true,
      metaKey: true,
    });
  }
  static get isInAutomation() {
    return shadow(this, "isInAutomation", false);
  }
}
const PDFViewerApplication = {
  initialBookmark: document.location.hash.substring(1),
  _initializedCapability: createPromiseCapability(),
  _fellback: false,
  appConfig: null,
  pdfDocument: null,
  pdfLoadingTask: null,
  printService: null,