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--- a/src/qtgui/rclmain_w.h
+++ b/src/qtgui/rclmain_w.h
@@ -84,6 +84,7 @@
     virtual void showAboutDialog();
     virtual void showMissingHelpers();
     virtual void startManual();
+    virtual void startManual(const string&);
     virtual void showDocHistory();
     virtual void showExtIdxDialog();
     virtual void showUIPrefs();