title: Bootstrap textarea out of viewport when change width with transition
body: <p>I'm facing an odd behaviour with Bootstrap.</p>
  
  <p>When I change the width of a textarea with CSS transition or jQuery animate, it expands out of the viewport until the animation is complete.</p>
  
  <p>HTML</p>
  
  <pre><code>&lt;nav class="navbar navbar-default"&gt;
    &lt;div class="container-fluid"&gt;
      &lt;div class="collapse navbar-collapse"&gt;
        &lt;ul class="nav navbar-nav navbar-right"&gt;
          &lt;li class="dropdown"&gt;
            &lt;a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false"&gt;Dropdown &lt;span class="caret"&gt;&lt;/span&gt;&lt;/a&gt;
            &lt;ul class="dropdown-menu"&gt;
              &lt;li class="navbar-text"&gt;
  
  
                &lt;form&gt;
                  &lt;div class="form-group"&gt;
                    &lt;textarea class="form-control"&gt;&lt;/textarea&gt;
                  &lt;/div&gt;
                &lt;/form&gt;
  
  
              &lt;/li&gt;
            &lt;/ul&gt;
          &lt;/li&gt;
        &lt;/ul&gt;
      &lt;/div&gt;&lt;!-- /.navbar-collapse --&gt;
    &lt;/div&gt;&lt;!-- /.container-fluid --&gt;
  &lt;/nav&gt;
  </code></pre>
  
  <p>CSS</p>
  
  <pre><code>textarea {
    width:100px;
  }
  textarea:focus {
    transition: 2s all;
    width:500px;
  }
  </code></pre>
  
  <p>Here is a Fiddle for demonstration:
  <a href="https://jsfiddle.net/hqm9urey/2/" rel="nofollow noreferrer">https://jsfiddle.net/hqm9urey/2/</a></p>
  
  <hr>
  
  <p>I couldn't reproduce it only with float:right:
  <a href="https://jsfiddle.net/05ba14bs/1/" rel="nofollow noreferrer">https://jsfiddle.net/05ba14bs/1/</a></p>
  
  <p>HTML</p>
  
  <pre><code>&lt;div&gt;
    &lt;textarea&gt;&lt;/textarea&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>CSS</p>
  
  <pre><code>div {
    float:right;
  }
  textarea {
    width:100px;
  }
  textarea:focus {
    transition: 2s all;
    width:500px;
  }
  </code></pre>