diff --git a/core/lib/Drupal/Core/Datetime/Element/Datetime.php b/core/lib/Drupal/Core/Datetime/Element/Datetime.php
index 44a3949..b52e28e 100644
--- a/core/lib/Drupal/Core/Datetime/Element/Datetime.php
+++ b/core/lib/Drupal/Core/Datetime/Element/Datetime.php
@@ -247,12 +247,17 @@ public static function processDatetime(&$element, FormStateInterface $form_state
         $html5_min->setDate($range[0], 1, 1)->setTime(0, 0, 0);
         $html5_max = clone($date);
         $html5_max->setDate($range[1], 12, 31)->setTime(23, 59, 59);
-
-        $extra_attributes += array(
-          'min' => $html5_min->format($date_format, $format_settings),
-          'max' => $html5_max->format($date_format, $format_settings),
-        );
       }
+      else {
+        $range = static::datetimeRangeYears($element['#date_year_range']);
+        $html5_min = DrupalDateTime::createFromFormat(DrupalDateTime::FORMAT, $range[0] . '-01-01 00:00:00');
+        $html5_max = DrupalDateTime::createFromFormat(DrupalDateTime::FORMAT, $range[1] . '-12-31 23:59:59');
+      }
+
+      $extra_attributes += array(
+        'min' => $html5_min->format($date_format, $format_settings),
+        'max' => $html5_max->format($date_format, $format_settings),
+      );
 
       $element['date'] = array(
         '#type' => 'date',
diff --git a/core/modules/system/src/Tests/Form/DatetimeTest.php b/core/modules/system/src/Tests/Form/DatetimeTest.php
index 782f361..1f207d8 100644
--- a/core/modules/system/src/Tests/Form/DatetimeTest.php
+++ b/core/modules/system/src/Tests/Form/DatetimeTest.php
@@ -43,12 +43,16 @@ function testFormDatetimeMinMax() {
       'datetime[time]' => '01:02:03',
     ];
 
-    // OK, these are the default values.
-    $this->drupalPostForm(NULL, $edit, 'Submit');
-    $this->assertFieldByXPath('//div[@id="edit-datetime"]//input[@type="date" and @min="1900-01-01" and @max="2050-12-31"]', '1776-07-14', 'Found input[@type="date" and @min="1900-01-01" and @max="2050-12-31"]');
-
-    // This makes no sense.
+    $this->drupalPostForm('form-test/datetime', $edit, 'Submit');
     $this->assertFieldByXPath('//div[@id="edit-datetime"]//input[@type="date" and @min="1776-01-01" and @max="2050-12-31"]', '1776-07-14', 'Found input[@type="date" and @min="1776-01-01" and @max="2050-12-31"]');
+
+    $edit = [
+      'datetime[date]' => '2134-07-14',
+      'datetime[time]' => '01:02:03',
+    ];
+
+    $this->drupalPostForm('form-test/datetime', $edit, 'Submit');
+    $this->assertFieldByXPath('//div[@id="edit-datetime"]//input[@type="date" and @min="1900-01-01" and @max="2134-12-31"]', '2134-07-14', 'Found input[@type="date" and @min="1900-01-01" and @max="2134-07-14"]');
   }
 
 }