message: Check the value returned by getState().
diff: @@ -304,8 +304,10 @@ export class Viewer {
  switch (e.data.type) {
  case 'initialized': {
  const state = vsStore.getState();
  + if (state) {
  state.type = 'restore_state';
  iframe.contentWindow.postMessage(state, '*');
  + }
  break;
  }
  case 'keyboard_event': {
  