Index: trunk/data/validator/deprecated.mapcss
===================================================================
--- trunk/data/validator/deprecated.mapcss	(revision 15648)
+++ trunk/data/validator/deprecated.mapcss	(revision 15715)
@@ -1879,2 +1879,10 @@
   group: tr("deprecated tagging");
 }
+
+/* #18571 */
+*[unnamed=yes] {
+  throwWarning: tr("{0} is deprecated", "{0.tag}");
+  suggestAlternative: "noname=yes";
+  fixChangeKey: "unnamed => noname";
+  group: tr("deprecated tagging");
+}