diff --git a/core/themes/seven/css/base/elements.css b/core/themes/seven/css/base/elements.css
index 4da963a3912..2599a0f5866 100644
--- a/core/themes/seven/css/base/elements.css
+++ b/core/themes/seven/css/base/elements.css
@@ -30,9 +30,6 @@ summary,
   text-transform: uppercase;
   font-weight: bold;
 }
-.simpletest-results-form summary {
-  text-transform: none;
-}
 
 /**
  * Reusable heading classes are included to help modules change the styling of
diff --git a/core/themes/stable/templates/admin/simpletest-result-summary.html.twig b/core/themes/stable/templates/admin/simpletest-result-summary.html.twig
deleted file mode 100644
index 55233256216..00000000000
--- a/core/themes/stable/templates/admin/simpletest-result-summary.html.twig
+++ /dev/null
@@ -1,20 +0,0 @@
-{#
-/**
- * @file
- * Theme override for simpletest result summaries.
- *
- * Available variables:
- * - label: An optional label to be rendered before the results.
- * - items: Pluralized summaries for each result type (number of passes, fails,
- *   exceptions, and debug messages).
- * - pass: The number of passes.
- * - fail: The number of fails.
- * - exception: The number of exceptions.
- * - debug: The number of debug messages.
- *
- * @see template_preprocess_simpletest_result_summary()
- */
-#}
-<div class="simpletest-{{ fail + exception == 0 ? 'pass' : 'fail' }}">
-  {{ label }} {{ items|join(', ') }}
-</div>