diff -r d30ff49d4a94 -r 3d3aa4dd6a32 web/data/cubicweb.css
--- a/web/data/cubicweb.css	Mon Jun 02 12:29:37 2014 +0200
+++ b/web/data/cubicweb.css	Mon Jun 02 12:37:52 2014 +0200
@@ -204,6 +204,11 @@
 }
 
 /* copied verbatim from bootstrap 3.0 */
+.invisible {
+  visibility: hidden;
+}
+
+/* copied verbatim from bootstrap 3.0 */
 .list-unstyled {
   padding-left: 0;
   list-style: none;