diff --git a/src/GUI/previewwindow.cpp b/src/GUI/previewwindow.cpp
index 5a4ce47df..7c4c5b694 100644
--- a/src/GUI/previewwindow.cpp
+++ b/src/GUI/previewwindow.cpp
@@ -3,6 +3,7 @@
 #include <QPainter>
 #include <QMouseEvent>
 #include <QNetworkReply>
+#include <QDebug>
 
 const int BORDER_SIZE = 16;