diff --git a/bedstead.c b/bedstead.c
index 3c5c890..14b1deb 100644
--- a/bedstead.c
+++ b/bedstead.c
@@ -3889,8 +3889,10 @@ dogsub(void)
 		printf("<Script><DefaultLangSys>\n");
 		TTXI("ReqFeatureIndex", 0xffff); /* No required feature. */
 		for (j = 0; j < lenof(gsub_features); j++)
-			if (gsub_features[j].scripts & gsub_scripts[i].flag)
+			if (gsub_features[j].scripts & gsub_scripts[i].flag) {
+				printf("<!-- %s --> ", gsub_features[j].tag);
 				TTXI("FeatureIndex", j);
+			}
 		printf("</DefaultLangSys></Script>\n");
 		printf("</ScriptRecord>\n");
 	}