diff -u b/core/modules/system/src/Element/StatusReport.php b/core/modules/system/src/Element/StatusReport.php
--- b/core/modules/system/src/Element/StatusReport.php
+++ b/core/modules/system/src/Element/StatusReport.php
@@ -67,7 +67,7 @@
    *
    * @return array
    */
-  protected static function getServerities() {
+  public static function getServerities() {
     return [
       REQUIREMENT_INFO => [
         'title' => t('Checked'),
diff -u b/core/modules/system/src/Element/StatusReportPage.php b/core/modules/system/src/Element/StatusReportPage.php
--- b/core/modules/system/src/Element/StatusReportPage.php
+++ b/core/modules/system/src/Element/StatusReportPage.php
@@ -10,7 +10,7 @@
  *
  * @RenderElement("status_report_page")
  */
-class StatusReportPage extends StatusReport {
+class StatusReportPage extends RenderElement {
 
   /**
    * {@inheritdoc}
@@ -90,7 +90,7 @@
       ],
     ];
 
-    $severities = static::getServerities();
+    $severities = StatusReport::getServerities();
     foreach ($element['#requirements'] as $key => &$requirement) {
       $severity = $severities[REQUIREMENT_INFO];
       if (isset($requirement['severity'])) {
only in patch2:
unchanged:
--- a/core/themes/seven/css/theme/maintenance-page.css
+++ b/core/themes/seven/css/theme/maintenance-page.css
@@ -142,7 +142,7 @@
   }
   .layout-container {
     margin: 0 auto;
-    max-width: 770px;
+    min-height: 75%;
     width: 75%;
     border-radius: 5px;
     box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);