title: Can I use multiple selectors in :host() argument?
body: <p>This is working:</p>
  <pre class="lang-css prettyprint-override"><code>:host(.foo) .title,
  :host(.bar) .title {
    ...
  }
  </code></pre>
  <p>I was expecting this to work, but it didn't:</p>
  <pre class="lang-css prettyprint-override"><code>:host(.foo, .bar) .title {
    ...
  }
  </code></pre>
  <p>Am I missing something? Or is this a browser bug? I'm using Firefox 100.0</p>