https://github.com/kovidgoyal/calibre/commit/30b66dc452d3c08c7e10cc95498e131348d7bbfb
Index: src/calibre/headless/headless_integration.h
--- src/calibre/headless/headless_integration.h.orig
+++ src/calibre/headless/headless_integration.h
@@ -3,7 +3,6 @@
 #include <qpa/qplatformintegration.h>
 #include <qpa/qplatformscreen.h>
 #include <qpa/qplatformservices.h>
-#include <QtGui/private/qgenericunixservices_p.h>
 #include <QScopedPointer>
 
 QT_BEGIN_NAMESPACE
