Bookmarklet to display and synchronously scroll multiple subdomains

confere.js

javascript:void((function($)
{
  var domain = 'example.com';
  var subdomains = ['www', 'dev'];
  if (!jQuery || location.hostname.indexOf(domain) < 0) {
    return false;
  }

  var row_height = 100 / subdomains.length;
  var $rows = $([]);
  var label_css = {
    position: 'absolute',
    color: '#fff',
    padding: '0 .25em',
    opacity: '.1',
    background: '#000',
    textDecoration: 'none',
    font: '10px sans-serif'
  };
  var iframe_css = {
    width: '100%',
    height: '2400px',
    borderStyle: 'none',
    background: '#fff'
  };
  $.each(subdomains, function(i, site)
  {
    var subdomain = subdomains[i];
    var host = subdomain + '.' + domain;
    if (location.port) {
      host += ':' + location.port;
    }
    var uri = location.pathname + location.search + location.hash;
    var url = location.protocol + '//' + host + uri;
    var $row = $('<div>').css({
      height: row_height + '%',
      overflowY: 'scroll'
    });
    $('<a>', {
      href: url
    })
    .text(host)
    .css(label_css)
    .appendTo($row);
    $('<iframe>', {
      src: url,
      name: subdomain
    })
    .css(iframe_css)
    .appendTo($row);
    $rows = $rows.add($row);
  });

  $rows.each(function()
  {
    var $other_rows = $rows.not(this);
    this.onscroll = function(e)
    {
      var st = this.scrollTop;
      $other_rows.each(function()
      {
        this.scrollTop = st;
      });
    }
  });
  $('body').html('').append($rows);
  $('html, body').css({
    height: '100%'
  });
})(jQuery));