title: Bootstrap 4 mr-auto not working correctly
body: <p>I have a snippet:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous"&gt;
  
  &lt;header&gt;
    &lt;div class="container"&gt;
      &lt;div class="row"&gt;
        &lt;div class="col-lg-3"&gt;
          &lt;div class="logo"&gt;
            &lt;img src="#" alt=" logotype"&gt;
          &lt;/div&gt;
        &lt;/div&gt;
        &lt;div class="col-lg-9"&gt;
          &lt;div class="head-buttons mr-auto"&gt;
            &lt;a href=""&gt;Русский&lt;/a&gt;
            &lt;div class="auth-buttons"&gt;
              &lt;button&gt;Войти&lt;/button&gt;
              &lt;button&gt;Регистрация&lt;/button&gt;
            &lt;/div&gt;
          &lt;/div&gt;
        &lt;/div&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/header&gt;</code></pre>
  </div>
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  </p>
  
  <p>I want col-lg-9 all content in this div align to right. Why <code>mr-auto</code> is not working? How I can fix it? I tried and <code>justify-content-end</code> on row, not working.. </p>