diff --git a/core/modules/system/system.modules.js b/core/modules/system/system.modules.js
index 4d97652..ad8fa23 100644
--- a/core/modules/system/system.modules.js
+++ b/core/modules/system/system.modules.js
@@ -39,8 +39,8 @@ function showModuleRow (index, row) {
         $rows.each(showModuleRow);
 
         // Hide the package <details> if they don't have any visible rows.
-        // Note that we first show() all <details> to be able to use ':visible'.
-        $details.show().each(hidePackageDetails);
+        // Note that we first open all <details> to be able to use ':visible'.
+        $details.attr('open', 'open').each(hidePackageDetails);
       }
       else {
         $rowsAndDetails.show();