diff -u b/core/modules/system/src/Tests/Theme/FunctionsTest.php b/core/modules/system/src/Tests/Theme/FunctionsTest.php
--- b/core/modules/system/src/Tests/Theme/FunctionsTest.php
+++ b/core/modules/system/src/Tests/Theme/FunctionsTest.php
@@ -211,7 +211,7 @@
     $this->assertThemeOutput('inline_list', $variables, $expected, '%callback sanitizes user-provided separators.');
   }
 
-    /**
+  /**
    * Tests links.html.twig.
    */
   function testLinks() {
diff -u b/core/modules/system/templates/inline-list.html.twig b/core/modules/system/templates/inline-list.html.twig
--- b/core/modules/system/templates/inline-list.html.twig
+++ b/core/modules/system/templates/inline-list.html.twig
@@ -4,10 +4,9 @@
  * Default theme implementation for an inline list of items.
  *
  * Available variables:
- * - items: An array of items.
- * - separator: A string to separate list items.
- * - empty: A message to display when there are no items. Allowed value is a
- *   string or render array.
+ * - items: An list of items.
+ * - separator: A delimiter to separate the items in the list.
+ * - empty: A message to display when there are no items.
  *
  * @see template_preprocess_inline_list()
  *