Backport of

https://github.com/KDE/trojita/commit/2869c385e72932cbed7398742b8a4d5e3feda765

--- a/src/Gui/Window.cpp
+++ b/src/Gui/Window.cpp
@@ -32,6 +32,7 @@
 #include <QKeyEvent>
 #include <QMenuBar>
 #include <QMessageBox>
+#include <QPainterPath>
 #include <QProgressBar>
 #include <QScrollBar>
 #include <QSplitter>
