title: LESS extend is not working for the imported css
body: <p>I'm trying to combine class names in to one using LESS extend mixin and this simple example is not giving expected results:</p>
  
  <pre><code>@import (less) "//netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css";
  
  .todoFlag:extend(.fa .fa-flag all) {
      color: red;
  }
  </code></pre>
  
  <p>The <code>.fa-flag</code> class above in imported css has only one selector like this:</p>
  
  <pre><code>.fa-flag:before {
    content: "\f024";
  }
  </code></pre>
  
  <p>The result of compilation is this:</p>
  
  <pre><code>.todoFlag {
    color: red;
  }
  </code></pre>
  
  <p>I was expecting <code>.todoFlag</code> will have <code>:before</code> due to extend but above is the only lines generated for todoFlag in compiled css.</p>
  
  <p>Am I using the extend correctly? Does extend works on classes imported like above?</p>