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--- a/src/qtgui/rclmain_w.h
+++ b/src/qtgui/rclmain_w.h
@@ -82,6 +82,7 @@
     virtual void showSortDialog();
     virtual void showSpellDialog();
     virtual void showAboutDialog();
+    virtual void showMissingHelpers();
     virtual void startManual();
     virtual void showDocHistory();
     virtual void showExtIdxDialog();