title: How to end a 'debug' mode?
body: <p>In RStudio, I started a debug mode by</p>
  
  <pre><code>debug(ls)
  ls()
  </code></pre>
  
  <p>Then I do not know how to end this mode. 
  The prompt changed to </p>
  
  <pre><code>Browse[2]&gt;
  </code></pre>
  
  <p>How can I end this debugging mode?</p>