diff --git a/src/network/network_content_gui.cpp b/src/network/network_content_gui.cpp
--- a/src/network/network_content_gui.cpp
+++ b/src/network/network_content_gui.cpp
@@ -64,7 +64,7 @@ struct ContentTextfileWindow : public Te
 		}
 	}
 
-	/* virtual */ void SetStringParameters(int widget) const
+	void SetStringParameters(int widget) const override
 	{
 		if (widget == WID_TF_CAPTION) {
 			SetDParam(0, this->GetTypeString());