diff --git a/core/modules/system/system.admin.inc b/core/modules/system/system.admin.inc
index 7271ed1..e8f0602 100644
--- a/core/modules/system/system.admin.inc
+++ b/core/modules/system/system.admin.inc
@@ -179,7 +179,7 @@ function template_preprocess_admin_page(&$variables) {
   $stripe = 0;
   foreach ($variables['blocks'] as $block) {
     $block = (array) $block;
-    if ($block['show'] = !empty($block['content'])) {
+    if ($block['show'] = !empty($block['content']['#content'])) {
       if (empty($block['position'])) {
         // Perform automatic striping.
         $block['position'] = ++$stripe % 2 ? 'left' : 'right';
diff --git a/core/modules/system/templates/admin-page.html.twig b/core/modules/system/templates/admin-page.html.twig
index 5a7d9b1..73cae67 100644
--- a/core/modules/system/templates/admin-page.html.twig
+++ b/core/modules/system/templates/admin-page.html.twig
@@ -9,7 +9,6 @@
  *   right. Contains:
  *   - blocks: A list of blocks within a container.
  *
- *
  * @see template_preprocess_admin_page()
  *
  * @ingroup themeable