Index: src/frontends/qt4/GuiDocument.cpp
===================================================================
--- src/frontends/qt4/GuiDocument.cpp	(revision b4d885ac6968df4a705d395069ea2310f10c122b)
+++ src/frontends/qt4/GuiDocument.cpp	(revision 1a4404944bf5830164435b0dedb6f6bee9c7371b)
@@ -69,9 +69,10 @@
 
 #include <QAbstractItemModel>
-#include <QHeaderView>
+#include <QButtonGroup>
 #include <QColor>
 #include <QColorDialog>
 #include <QCloseEvent>
 #include <QFontDatabase>
+#include <QHeaderView>
 #include <QScrollBar>
 #include <QTextBoundaryFinder>