JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<script src="//code.jquery.com/jquery-1.12.0.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap-theme.min.css">
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu" style="display: block; position: static; margin-bottom: 5px; *width: 180px;">
  <li class="menu-item dropdown dropdown-submenu">
    <data-some-random-tag><!-- <--- this tag was addded -->
      <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 1</a>
      <ul class="dropdown-menu">
        <li class="menu-item ">
          <a href="#">Link 2</a>
        </li>
        <li class="menu-item dropdown dropdown-submenu">
          <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 2</a>
          <ul class="dropdown-menu">
            <li>
              <a href="#">Link 3</a>
            </li>
            <li class="menu-item dropdown dropdown-submenu">
              <a ref="#" class="dropdown-toggle" data-toggle="dropdown">Level 3</a>
              <ul class="dropdown-menu">
                <li>
                  <a href="#">Link 4</a>
                </li>
              </ul>
            </li>
          </ul>
        </li>
      </ul>
    </data-some-random-tag>
  </li>
</ul>

CSS

.dropdown-submenu {
  position: relative;
}

.dropdown-submenu>.dropdown-menu {
  top: 0;
  left: 100%;
  margin-top: -6px;
  margin-left: -1px;
  -webkit-border-radius: 0 6px 6px 6px;
  -moz-border-radius: 0 6px 6px 6px;
  border-radius: 0 6px 6px 6px;
}

.dropdown-submenu:hover>.dropdown-menu {
  display: block;
}

.dropdown-submenu>a:after {
  display: block;
  content: " ";
  float: right;
  width: 0;
  height: 0;
  border-color: transparent;
  border-style: solid;
  border-width: 5px 0 5px 5px;
  border-left-color: #cccccc;
  margin-top: 5px;
  margin-right: -10px;
}

.dropdown-submenu:hover>a:after {
  border-left-color: #ffffff;
}

.dropdown-submenu.pull-left {
  float: none;
}

.dropdown-submenu.pull-left>.dropdown-menu {
  left: -100%;
  margin-left: 10px;
  -webkit-border-radius: 6px 0 6px 6px;
  -moz-border-radius: 6px 0 6px 6px;
  border-radius: 6px 0 6px 6px;
}