diff --git a/indra/newview/llfloaterhowto.h b/indra/newview/llfloaterhowto.h
index 15fc43335af67b23da61958f4dfc8d47e3f9d599..fa1d9cace0040020dc9730ab110ca95631f2f840 100644
--- a/indra/newview/llfloaterhowto.h
+++ b/indra/newview/llfloaterhowto.h
@@ -42,12 +42,14 @@ class LLFloaterHowTo :
 
     LLFloaterHowTo(const Params& key);
 
-    /*virtual*/ void onOpen(const LLSD& key);
+    void onOpen(const LLSD& key) override;
 
     static LLFloaterHowTo* getInstance();
 
+    bool matchesKey(const LLSD& key) override { return true; /*single instance*/ };
+
 private:
-    /*virtual*/ BOOL postBuild();
+    BOOL postBuild() override;
 };
 
 #endif  // LL_LLFLOATERHOWTO_H