message: The internal PDF viewer should not get focus when initially loaded.
diff: @@ -282,13 +282,10 @@ export class Viewer {
  <body><iframe id="preview-panel" class="preview-panel" src="${iframeSrcUrl}" style="position:absolute; border: none; left: 0; top: 0; width: 100%; height: 100%;">
  </iframe>
  <script>
  - // when the iframe loads, or when the tab gets focus again later, move the
  + // When the tab gets focus again later, move the
  // the focus to the iframe so that keyboard navigation works in the pdf.
  - //
  - // Note: this works on first load, or when navigating between groups, but not when
  - // navigating between tabs of the same group for some reason!
  const iframe = document.getElementById('preview-panel');
  - window.onfocus = iframe.onload = function() {
  + window.onfocus = function() {
  setTimeout(function() { // doesn't work immediately
  iframe.contentWindow.focus();
  }, 100);
  