code: function receiveIframeMessage(event) {
    // does the origin sending the message match the current host? if not dev/null the request
    if (
      window.location.protocol !== 'file:' &&
      event.origin !== window.location.protocol + '//' + window.location.host
    ) {
      return;
    }
  
    let path;
    let data = {};
    try {
      data = typeof event.data !== 'string' ? event.data : JSON.parse(event.data);
    } catch (e) {
      // @todo: how do we want to handle exceptions like these?
    }
  
    if (data.event !== undefined && data.event === 'patternLab.updatePath') {
      if (window.patternData.patternPartial !== undefined) {
        // handle patterns and the view all page
        const re = /(patterns|snapshots)\/(.*)$/;
        path =
          window.location.protocol +
          '//' +
          window.location.host +
          window.location.pathname.replace(re, '') +
          data.path +
          '?' +
          Date.now();
        window.location.replace(path);
      } else {
        // handle the style guide
        path =
          window.location.protocol +
          '//' +
          window.location.host +
          window.location.pathname.replace(
            'styleguide/html/styleguide.html',
            ''
          ) +
          data.path +
          '?' +
          Date.now();
        window.location.replace(path);
      }
    } else if (data.event !== undefined && data.event === 'patternLab.reload') {
      // reload the location if there was a message to do so
      window.location.reload();
    }
  }
docs: watch the iframe source so that it can be sent back to everyone else.