diff -u b/core/lib/Drupal/Core/Render/theme.api.php b/core/lib/Drupal/Core/Render/theme.api.php
--- b/core/lib/Drupal/Core/Render/theme.api.php
+++ b/core/lib/Drupal/Core/Render/theme.api.php
@@ -257,10 +257,10 @@
  * Render arrays (at any level of the hierarchy) will usually have one of the
  * following properties defined:
  * - #type: Specifies that the array contains data and options for a particular
- *   type of "render element" (for example, 'form', for an HTML form; 'textfield',
- *   'submit', for HTML form element types; 'table', for a table with
- *   rows, columns, and headers). See @ref elements below for more on render
- *   element types.
+ *   type of "render element" (for example, 'form', for an HTML form;
+ *   'textfield', 'submit', for HTML form element types; 'table', for a table
+ *   with rows, columns, and headers). See @ref elements below for more on
+ *   render element types.
  * - #theme: Specifies that the array contains data to be themed by a particular
  *   theme hook. Modules define theme hooks by implementing hook_theme(), which
  *   specifies the input "variables" used to provide data and options; if a