diff --git a/scripts/speculator/main.go b/scripts/speculator/main.go
index 7f86bd62..e1898d7e 100644
--- a/scripts/speculator/main.go
+++ b/scripts/speculator/main.go
@@ -385,7 +385,7 @@ func main() {
 	}
 	s := server{masterCloneDir}
 	http.HandleFunc("/spec/", forceHTML(s.serveSpec))
-	http.HandleFunc("/diff/rst/", forceHTML(s.serveRSTDiff))
+	http.HandleFunc("/diff/rst/", s.serveRSTDiff)
 	http.HandleFunc("/diff/html/", forceHTML(s.serveHTMLDiff))
 	http.HandleFunc("/healthz", serveText("ok"))
 	http.HandleFunc("/", forceHTML(listPulls))