reverted:
--- b/core/modules/system/tests/themes/test_theme/test_theme.libraries.yml
+++ /dev/null
@@ -1,5 +0,0 @@
-global-styling:
-  version: VERSION
-  css:
-    base:
-      kitten.css: {}
diff -u b/core/themes/stark/stark.info.yml b/core/themes/stark/stark.info.yml
--- b/core/themes/stark/stark.info.yml
+++ b/core/themes/stark/stark.info.yml
@@ -1,6 +1,6 @@
 name: Stark
 type: theme
-description: 'An intentionally plain theme with almost no styling to demonstrate default Drupal’s HTML and CSS. Learn how to build a custom theme from Stark in the <a href="https://www.drupal.org/theme-guide">Theming Guide</a>.'
+description: 'An intentionally plain theme with no styling to demonstrate default Drupal’s HTML and CSS. Learn how to build a custom theme from Stark in the <a href="https://www.drupal.org/theme-guide">Theming Guide</a>.'
 package: Core
 version: VERSION
 core: 8.x