only in patch2:
unchanged:
--- a/core/modules/search/src/Tests/SearchConfigSettingsFormTest.php
+++ b/core/modules/search/src/Tests/SearchConfigSettingsFormTest.php
@@ -214,7 +214,7 @@ function testSearchModuleDisabling() {
    */
   public function testDefaultSearchPageOrdering() {
     $this->drupalGet('search');
-    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs primary'));
+    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs tabs--primary'));
     $this->assertIdentical((string) $elements[0]['href'], \Drupal::url('search.view_node_search'));
     $this->assertIdentical((string) $elements[1]['href'], \Drupal::url('search.view_user_search'));
   }
@@ -268,7 +268,7 @@ public function testMultipleSearchPages() {
 
     // Ensure both search pages have their tabs displayed.
     $this->drupalGet('search');
-    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs primary'));
+    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs tabs--primary'));
     $this->assertIdentical((string) $elements[0]['href'], _url('search/' . $first['path']));
     $this->assertIdentical((string) $elements[1]['href'], _url('search/' . $second['path']));
 
@@ -279,7 +279,7 @@ public function testMultipleSearchPages() {
     );
     $this->drupalPostForm('admin/config/search/pages', $edit, t('Save configuration'));
     $this->drupalGet('search');
-    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs primary'));
+    $elements = $this->xpath('//*[contains(@class, :class)]//a', array(':class' => 'tabs tabs--primary'));
     $this->assertIdentical((string) $elements[0]['href'], _url('search/' . $second['path']));
     $this->assertIdentical((string) $elements[1]['href'], _url('search/' . $first['path']));
 
only in patch2:
unchanged:
--- a/core/modules/system/css/system.theme.css
+++ b/core/modules/system/css/system.theme.css
@@ -424,12 +424,9 @@ ul.links a.active {
 /**
  * Markup generated by menu-local-tasks.html.twig.
  */
-div.tabs {
-  margin: 1em 0;
-}
 ul.tabs {
   list-style: none;
-  margin: 0 0 0.5em;
+  margin: 1em 0 0.5em;
   padding: 0;
 }
 .tabs > li {
only in patch2:
unchanged:
--- a/core/modules/system/src/Tests/Menu/LocalTasksTest.php
+++ b/core/modules/system/src/Tests/Menu/LocalTasksTest.php
@@ -30,7 +30,7 @@ class LocalTasksTest extends WebTestBase {
    */
   protected function assertLocalTasks(array $hrefs, $level = 0) {
     $elements = $this->xpath('//*[contains(@class, :class)]//a', array(
-      ':class' => $level == 0 ? 'tabs primary' : 'tabs secondary',
+      ':class' => $level == 0 ? 'tabs tabs--primary' : 'tabs tabs--secondary',
     ));
     $this->assertTrue(count($elements), 'Local tasks found.');
     foreach ($hrefs as $index => $element) {
only in patch2:
unchanged:
--- a/core/modules/user/src/Tests/UserRoleAdminTest.php
+++ b/core/modules/user/src/Tests/UserRoleAdminTest.php
@@ -30,7 +30,7 @@ function testRoleAdministration() {
     // Test presence of tab.
     $this->drupalGet('admin/people/permissions');
     $tabs = $this->xpath('//ul[@class=:classes and //a[contains(., :text)]]', array(
-      ':classes' => 'tabs primary',
+      ':classes' => 'tabs tabs--primary',
       ':text' => t('Roles'),
     ));
     $this->assertEqual(count($tabs), 1, 'Found roles tab');
only in patch2:
unchanged:
--- a/core/modules/views/src/Tests/Plugin/DisplayPageWebTest.php
+++ b/core/modules/views/src/Tests/Plugin/DisplayPageWebTest.php
@@ -84,7 +84,7 @@ public function testPageDisplayMenu() {
     $this->drupalGet('test_page_display_menu');
     $this->assertResponse(200);
     $element = $this->xpath('//ul[contains(@class, :ul_class)]//a[contains(@class, :a_class)]', array(
-      ':ul_class' => 'tabs primary',
+      ':ul_class' => 'tabs tabs--primary',
       ':a_class' => 'active',
     ));
     $this->assertEqual((string) $element[0], t('Test default tab'));
@@ -96,7 +96,7 @@ public function testPageDisplayMenu() {
     $this->drupalGet('test_page_display_menu/local');
     $this->assertResponse(200);
     $element = $this->xpath('//ul[contains(@class, :ul_class)]//a[contains(@class, :a_class)]', array(
-      ':ul_class' => 'tabs primary',
+      ':ul_class' => 'tabs tabs--primary',
       ':a_class' => 'active',
     ));
     $this->assertEqual((string) $element[0], t('Test local tab'));
only in patch2:
unchanged:
--- a/core/themes/seven/templates/menu-local-tasks.html.twig
+++ b/core/themes/seven/templates/menu-local-tasks.html.twig
@@ -19,12 +19,12 @@
   <h2 id="primary-tabs-title" class="visually-hidden">{{ 'Primary tabs'|t }}</h2>
   <nav role="navigation" class="is-horizontal is-collapsible" aria-labelledby="primary-tabs-title" data-drupal-nav-tabs>
     <button class="reset-appearance tabs__tab tabs__trigger" aria-label="{{ 'Primary tabs display toggle'|t }}" data-drupal-nav-tabs-trigger>&bull;&bull;&bull;</button>
-    <ul class="tabs primary clearfix" data-drupal-nav-tabs-target>{{ primary }}</ul>
+    <ul class="tabs tabs--primary clearfix" data-drupal-nav-tabs-target>{{ primary }}</ul>
   </nav>
 {% endif %}
 {% if secondary %}
   <h2 id="secondary-tabs-title" class="visually-hidden">{{ 'Secondary tabs'|t }}</h2>
   <nav role="navigation" class="is-horizontal" aria-labelledby="secondary-tabs-title" data-drupal-nav-tabs>
-    <ul class="tabs secondary clearfix">{{ secondary }}</ul>
+    <ul class="tabs tabs--secondary clearfix">{{ secondary }}</ul>
   </nav>
 {% endif %}