diff --git a/normalize.css b/normalize.css
index 12c6061..9f9a577 100644
--- a/normalize.css
+++ b/normalize.css
@@ -423,11 +423,18 @@ textarea {
  */
 
 details, /* 1 */
-menu,
-summary { /* 1 */
+menu {
   display: block;
 }
 
+/*
+ * Add the correct display in all browsers.
+ */
+
+summary {
+  display: list-item;
+}
+
 /* Scripting
    ========================================================================== */