 v-for="pm in postMessageEvents">
          <span v-if="pm.type === 'custom'">
            Tab: <strong>{{ pm.id }}</strong> sent:
            <span>{{ pm.msg }}</span>
          </span>
          <span v-if="pm.type === 'open'"> Tab: <strong>{{ pm.id }}</strong> Opened </span>
          <span v-if="pm.type === 'close'"> Tab: <strong>{{ pm.id }}</strong> Closed </span>
        </li>
      </div>
    </div>
    <script src="../../node_modules/vue/dist/vue.js"></script>
    <script src="app.js"></script>
  </