diff --git a/qglview/openglwindow.cpp b/qglview/openglwindow.cpp
index fea547c..375d1fa 100644
--- a/qglview/openglwindow.cpp
+++ b/qglview/openglwindow.cpp
@@ -11,7 +11,7 @@ OpenGLWindow::OpenGLWindow(QWindow *parent)
 	, m_context(nullptr)
 	, m_device(nullptr)
 {
-	setFlag(Qt::FramelessWindowHint);
+	setFlags(flags() | Qt::FramelessWindowHint);
 	setSurfaceType(QWindow::OpenGLSurface);
 	QSurfaceFormat format = QSurfaceFormat::defaultFormat();
 //	qDebug() << format;