diff --git a/ui/wolf.lib.html b/ui/wolf.lib.html
index 1576753..59c587f 100644
--- a/ui/wolf.lib.html
+++ b/ui/wolf.lib.html
@@ -10,35 +10,6 @@
     </ui>
 </wolf:control>
 
-<wolf:control id="button2">
-    <attr mandatory="true">icon</attr>
-    <attr>text</attr>
-    <event>click</event>
-    <ui id="main">
-        <button class="button" event:click="btnClick"><i class="material-icons">$icon</i>$text</button>
-    </ui>
-    <script>
-        'use strict';
-
-        function render() {
-            return control.ui("main");
-        }
-
-        function btnClick(element, event) {
-            var ctrl = element.getController();
-            var m = ctrl[control.get("event:click")];
-            if (!m)
-                throw new Error("Me las pagarás");
-            m(element, event);
-        }
-
-        return {
-            render: render,
-            btnClick: btnClick
-        }
-    </script>
-</wolf:control>
-
 <!-- usage -->
 <!--
 <wolf:button click="goAdd" icon="add" />
diff --git a/ui/wolf.ui.js b/ui/wolf.ui.js
index ad865bd..8f488ad 100644
--- a/ui/wolf.ui.js
+++ b/ui/wolf.ui.js
@@ -196,6 +196,8 @@
             function renderControlDOM(ext) {
                 var tux = ext.customController.render();
                 var ux = [];
+                if (!tux)
+                    return [];
                 if (!Array.isArray(tux))
                     tux = [tux];
                 for (var i in tux)
@@ -275,7 +277,7 @@
                                 var script = c.c[0].value;
                                 if (script && (typeof script != "string" || script.indexOf("use strict") < 1))
                                     throw new Error("Control definition wolf:" + id + " script 'use strict'; mandatory");
-                                scriptFactory = new Function('control', `${script};\n//# sourceURL=_CONTROL_${id}`);
+                                scriptFactory = new Function('control', `${script};\n//# sourceURL=wolf:${id}`);
                                 break;
                             }
                             default: