diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 769e34c..665ca73 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -568,9 +568,8 @@ function template_preprocess_datetime_wrapper(&$variables) {
  *
  * @param array $variables
  *   An associative array containing:
- *   - links: An associative array of links to be themed. The key for each link
- *     is used as its CSS class. Each link should be itself an array, with the
- *     following elements:
+ *   - links: An array of links to be themed. Each link should be itself an
+ *     array, with the following elements:
  *     - title: The link text.
  *     - url: (optional) The url object to link to. If omitted, no a tag is
  *       printed out.
diff --git a/core/themes/stable/stable.theme b/core/themes/stable/stable.theme
index aafe570..663667a 100644
--- a/core/themes/stable/stable.theme
+++ b/core/themes/stable/stable.theme
@@ -6,7 +6,9 @@
  * Implements template_preprocess_links().
  */
 function stable_preprocess_links(&$variables) {
-  // @TODO Deprecate this feature of adding a class based on the key in 9.x.
+  // @deprecated in Drupal 8.0.x and will be removed before 9.0.0. This feature
+  // of adding a class based on the associative key can cause CSS class
+  // name conflicts.
   if (!empty($variables['links'])) {
     foreach ($variables['links'] as $key => $value) {
       if (!is_numeric($key)) {