message: Remove unneeded window attribute in custom paint widget
  * This was having some unpleasant knock-on effects in Qt that caused other
  controls in the panels to fail to render properly.
diff: @@ -49,7 +49,6 @@ CustomPaintWidget::CustomPaintWidget(QWidget *parent) : QWidget(parent)
  m_Tag = QFormatStr("custompaint%1").arg((uintptr_t) this);
  setAttribute(Qt::WA_OpaquePaintEvent);
  - setAttribute(Qt::WA_PaintOnScreen);
  m_Dark = Formatter::DarkCheckerColor();
  m_Light = Formatter::LightCheckerColor();
  