title: Remove extra blank row from navbarPage Shiny layout
body: <p>I'm developing a Shiny app using both navbarPage and sidebarPanel layouts. However, an extra empty row keeps being appended right below the navigation bar (see image below). In the HTML file, I can clearly see the culprit:</p>
  
  <pre><code>&lt;div class="row"&gt;&amp;nbsp;&lt;/div&gt;
  </code></pre>
  
  <p>However, I can't seem to figure out which part of my R code is causing that extra row to be created. For the reference, below is a minimum <code>ui.R</code> code that illustrates the issue:</p>
  
  <pre><code>shinyUI(fluidPage(
    navbarPage('Minimum Example',
      tabPanel('Tab1',
        sidebarLayout(
          sidebarPanel(br()),
          mainPanel(br())
        )
      )
  )))    
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/8kQI4.jpg" alt="Extra blank row below navigation tab and above sidebarpanel">    </p>