title: Spyder 5 No QCoreApplication instance found. Application patches not applied
body: <p>I get the following error after having upgraded to <code>Spyder 5</code></p>
  <pre><code>  No QCoreApplication instance found. Application patches not applied. You have to call load_stylesheet function after instantiation of QApplication to take effect. 
  </code></pre>
  <p>The interface also looks 'not nice' (I am guessing without the stylesheet).</p>
  <p><a href="https://i.stack.imgur.com/JNERu.png" rel="noreferrer"><img src="https://i.stack.imgur.com/JNERu.png" alt="Display 5.0 - 1" /></a></p>
  <p>Downgrading to Spyder 4 causes everything to appear in a single column (Code area, console, variable explorer etc, all one below other with ugly overlap to make it unusable).</p>
  <p>How do I go about fixing this?</p>