{ tab_title }}"}`;
          }
      });

      // set properties
      document.addEventListener("webviewerloaded", () => {
        PDFViewerApplicationOptions.set('disablePreferences', true); // needed otherwise settings are not overwritten
        PDFViewerApplicationOptions.set('disableHistory', true); // disable browsing history, clicking on chapters does not open new page
        PDFViewerApplicationOptions.set('viewOnLoad', 1  ); // disable remembering page
        PDFViewerApplicationOptions.set("wo