title: view.showMaximised() not working in PyQt5
body: <p>I am making a web browser using <code>PyQt5</code>. I am using the following code:</p>
  
  <pre class="lang-py prettyprint-override"><code>import PyQt5
  from PyQt5.QtCore import QUrl
  from PyQt5.QtWidgets import QApplication, QWidget
  from PyQt5.QtWebKitWidgets import QWebView , QWebPage
  from PyQt5.QtWebKit import QWebSettings
  from PyQt5.QtNetwork import *
  import sys
  from optparse import OptionParser
  
  class Browser(QWebView):
      def __init__(self):
          # QWebView
          self.view = QWebView.__init__(self)
          #self.view.setPage(MyBrowser())
          self.setWindowTitle('Loading...')
          self.titleChanged.connect(self.adjustTitle)
          #super(Browser).connect(self.ui.webView,QtCore.SIGNAL("titleChanged (const QString&amp;amp;)"), self.adjustTitle)
  
      def load(self,url):
          self.setUrl(QUrl(url))
  
      def adjustTitle(self):
          self.setWindowTitle(self.title())
  
  app = QApplication(sys.argv)
  view = Browser()
  view.showMaximized()
  view.load("https://duckduckgo.com")
  app.exec_()
  </code></pre>
  
  <p>However, this is what I get:<a href="https://i.stack.imgur.com/0Yj1x.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0Yj1x.png" alt="screenshot"></a></p>
  
  <p>Can someone please tell me where I am going wrong? Note that it is not a problem of the website. I have tried it with Wikipedia, Stack Overflow and Google. I am using PyQt5 version 5.10.1.</p>