title: Why does my stylesheet apply to one qtreewidget, but not another?
body: <p>I have two QTreeWidgets, and a stylesheet that is applied to both (via a common ancestor):</p>
  
  <pre><code>styleSheet += QString("QWidget:!active { ");
  styleSheet += QString("  selection-background-color: %1; ").arg(inactiveHighlight.name());
  styleSheet += QString("  selection-color: %1;            ").arg(inactiveHighlightText.name());
  styleSheet += QString("}\n");
  styleSheet += QString("QWidget:active { ");
  styleSheet += QString("  selection-background-color: %1; ").arg(activeHighlight.name());
  styleSheet += QString("  selection-color: %1;            ").arg(activeHighlightText.name());
  styleSheet += QString("}\n");
  </code></pre>
  
  <p>The first tree applied the selection colors, the other does not.</p>
  
  <p>I am using Qt 4.8.5 and have had this problem since Qt 4.6.3.</p>