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.
this.pdfLinkService.setHash(storedHash);
    }
    
    
    this.toolbar.setPageNumber(
      this.pdfViewer.currentPageNumber,
      this.pdfViewer.currentPageLabel
    );
    this.secondaryToolbar.setPageNumber(this.pdfViewer.currentPageNumber);
    if (!this.pdfViewer.currentScaleValue) {
      
      
      this.pdfViewer.currentScaleValue = DEFAULT_SCALE_VALUE;
    }
  },
  /**
   * @private
   */
  _cleanup() {
    if (!this.pdfDocument) {
      return; 
    }
    this.pdfViewer.cleanup();
    this.pdfThumbnailViewer.cleanup();
    
    this.pdfDocument.cleanup(
       this.pdfViewer.renderer === RendererType.SVG
    );
  },
  forceRendering() {