diff --git a/sources/diagramview.cpp b/sources/diagramview.cpp
index d8e0c9ca4..87fe9dedd 100644
--- a/sources/diagramview.cpp
+++ b/sources/diagramview.cpp
@@ -512,7 +512,7 @@ void DiagramView::mouseMoveEvent(QMouseEvent *e)
 #if TODO_LIST
 #pragma message("@TODO remove code for QT 6 or later")
 #endif
-	if (e->button() == Qt::MiddleButton)
+	if (e->buttons() == Qt::MiddleButton)
 #endif
 	{
 		QScrollBar *h = horizontalScrollBar();