title: How to use stylesheet_link_tag with sprockets 4?
body: <p>I have file app/assets/stylesheets/themes/plexa/home.sass</p>
  <ol>
  <li><p>Added to config/manifest.js</p>
  <p>//= link themes/plexa/home.css</p>
  </li>
  <li><p>Check <code>http://localhost:3000/assets/themes/plexa/home.css</code> - It works, I see css!</p>
  </li>
  <li><p>But if I add to rails layout:</p>
  </li>
  </ol>
  <p><code>stylesheet_link_tag &quot;themes/plexa/home&quot;</code> This doesn't work!</p>
  <p><strong>It raise rails exception: ActionView::Template::Error at /
  themes/plexa/home.css</strong></p>
  <p>Tried with debugger:</p>
  <pre><code>byebug) stylesheet_link_tag &quot;themes/plexa/home&quot;
  *** Sprockets::Rails::Helper::AssetNotPrecompiled Exception: themes/plexa/home.css
  </code></pre>
  <p>I read all sprockets docs and upgrade guide but doesn't understand why stylesheet_link_tag doesn't works ( Rails 5.1)</p>
  <p><strong>Update:</strong> = stylesheet_link_tag &quot;/assets/themes/plexa/home&quot; <strong>Works, but I doesn't understand why I need to setup assets path?</strong></p>