reverted:
--- b/core/modules/block/block.module
+++ a/core/modules/block/block.module
@@ -375,6 +375,9 @@
   $variables['attributes']['class'][] = 'block';
   $variables['attributes']['class'][] = drupal_html_class('block-' . $variables['configuration']['provider']);
 
+  // Add default class for block content.
+  $variables['content_attributes']['class'][] = 'content';
+
   // Create a valid HTML ID and make sure it is unique.
   if ($id = $variables['elements']['#block']->id()) {
     $variables['attributes']['id'] = drupal_html_id('block-' . $id);
reverted:
--- b/core/modules/block/src/Tests/BlockPreprocessUnitTest.php
+++ a/core/modules/block/src/Tests/BlockPreprocessUnitTest.php
@@ -52,11 +52,10 @@
     $variables['elements']['#derivative_plugin_id'] = $plugin->getDerivativeId();
     $variables['elements']['content'] = array();
 
+    // Test adding a class to the block content.
+    $variables['content_attributes']['class'][] = 'test-class';
-    // Test adding a class to the block.
-    $variables['attributes']['class'][] = 'test-class';
     template_preprocess_block($variables);
+    $this->assertEqual($variables['content_attributes']['class'], array('test-class', 'content'), 'Default .content class added to block content_attributes');
-
-    $this->assertEqual($variables['attributes']['class'], array('test-class', 'block', 'block-system'), 'Default .block and .block-system classes added to block');
   }
 
 }
reverted:
--- b/core/themes/bartik/css/style.css
+++ a/core/themes/bartik/css/style.css
@@ -407,6 +407,10 @@
   overflow: hidden;
   height: 1px;
 }
+.region-header .block .content {
+  margin: 0;
+  padding: 0;
+}
 .region-header .block ul {
   margin: 0;
   padding: 0;
@@ -466,6 +470,9 @@
 .region-header #block-user-login {
   width: auto;
 }
+.region-header #block-user-login .content {
+  margin-top: 2px;
+}
 .region-header #block-user-login .form-item {
   float: left; /* LTR */
   margin: 0;
@@ -886,21 +893,18 @@
   padding: 15px 20px;
   margin: 0 0 20px;
 }
+.sidebar h2 {
-.sidebar .block > h2 {
   margin: 0 0 0.5em;
   border-bottom: 1px solid #d6d6d6;
   padding-bottom: 5px;
   text-shadow: 0 1px 0 #fff;
+  font-size: 1.071em;
+  line-height: 1.2;
-  font-size: 1.171em;
-  line-height: 0.857;
 }
+.sidebar .block .content {
-.sidebar .block {
   font-size: 0.914em;
   line-height: 1.4;
 }
-.sidebar .block .contextual-links {
-  font-size: 1.010;
-}
 .sidebar tbody {
   border: none;
 }
@@ -968,12 +972,17 @@
 
 /* ------------------ Footer ------------------ */
 
+#footer-wrapper .block .content {
+  color: #c0c0c0;
+  color: rgba(255, 255, 255, 0.65);
+  font-size: 0.857em;
+}
+#footer-wrapper .block .content a {
-#footer-wrapper .block a {
   color: #fcfcfc;
   color: rgba(255, 255, 255, 0.8);
 }
+#footer-wrapper .block .content a:hover,
+#footer-wrapper .block .content a:focus {
-#footer-wrapper .block a:hover,
-#footer-wrapper .block a:focus {
   color: #fefefe;
   color: rgba(255, 255, 255, 0.95);
 }
@@ -982,18 +991,6 @@
   border: 1px solid #444;
   border-color: rgba(255, 255, 255, 0.1);
   padding: 10px;
-  color: #c0c0c0;
-  color: rgba(255, 255, 255, 0.65);
-  font-size: 0.857em;
-}
-#footer-wrapper .block .contextual .contextual-links a {
-  color: #333333;
-  font-size: 1em;
-  line-height: 1;
-}
-#footer-columns .block > h2 {
-  color: #3B3B3B;
-  font-size: 1.167em;
 }
 #footer-columns .block-menu,
 #footer .block {
@@ -1003,7 +1000,10 @@
 }
 #footer .block {
   margin: 0.5em 0;
+}
+#footer .block .content {
   padding: 0.5em 0;
+  margin-top: 0;
 }
 #footer .block > h2 {
   /* @extend .visually-hidden */
@@ -1023,26 +1023,26 @@
   padding-bottom: 3px;
   text-transform: uppercase;
 }
+#footer-columns .content {
+  margin-top: 0;
+}
 #footer-columns p {
   margin-top: 1em;
 }
+#footer-columns .content ul {
-#footer-columns ul {
   list-style: none;
   padding-left: 0; /* LTR */
   margin-left: 0;
 }
+[dir="rtl"] #footer-columns .content ul {
-[dir="rtl"] #footer-columns ul {
   padding-right: 0;
 }
+#footer-columns .content li {
-#footer-columns li {
   list-style: none;
   margin: 0;
   padding: 0;
 }
+#footer-columns .content li a {
-#footer-columns .contextual-links li {
-  line-height: 1;
-}
-#footer-columns li a {
   display: block;
   border-bottom: 1px solid #555;
   border-color: rgba(255, 255, 255, 0.15);
@@ -1050,11 +1050,11 @@
   padding: 0.8em 2px 0.8em 20px; /* LTR */
   text-indent: -15px;
 }
+[dir="rtl"] #footer-columns .content li a {
-[dir="rtl"] #footer-columns li a {
   padding: 0.8em 20px 0.8em 2px;
 }
+#footer-columns .content li a:hover,
+#footer-columns .content li a:focus {
-#footer-columns li a:hover,
-#footer-columns li a:focus {
   background-color: #1f1f21;
   background-color: rgba(255, 255, 255, 0.05);
   text-decoration: none;
only in patch2:
unchanged:
--- a/core/modules/block/src/Tests/BlockHtmlTest.php
+++ b/core/modules/block/src/Tests/BlockHtmlTest.php
@@ -48,7 +48,7 @@ function testHtml() {
     $this->assertFieldByXPath('//div[@id="block-test-html-block" and @data-custom-attribute="foo"]', NULL, 'HTML ID and attributes for test block are valid and on the same DOM element.');
 
     // Ensure expected markup for a menu block.
-    $elements = $this->xpath('//div[contains(@class, :div-class)]/div/ul[contains(@class, :ul-class)]/li', array(':div-class' => 'block-system', ':ul-class' => 'menu'));
+    $elements = $this->xpath('//div[contains(@class, :div-class)]/ul[contains(@class, :ul-class)]/li', array(':div-class' => 'block-system', ':ul-class' => 'menu'));
     $this->assertTrue(!empty($elements), 'The proper block markup was found.');
   }
 
only in patch2:
unchanged:
--- a/core/modules/block/src/Tests/BlockViewBuilderTest.php
+++ b/core/modules/block/src/Tests/BlockViewBuilderTest.php
@@ -86,11 +86,8 @@ public function testBasicRendering() {
     $expected[] = '<div id="block-test-block1" class="block block-block-test">';
     $expected[] = '  ';
     $expected[] = '    ';
-    $expected[] = '';
-    $expected[] = '  <div class="content">';
-    $expected[] = '          ';
-    $expected[] = '      </div>';
-    $expected[] = '</div>';
+    $expected[] = '      ';
+    $expected[] = '  </div>';
     $expected[] = '';
     $expected_output = implode("\n", $expected);
     $this->assertEqual(drupal_render($output), $expected_output);
@@ -114,11 +111,8 @@ public function testBasicRendering() {
     $expected[] = '  ';
     $expected[] = '      <h2>Powered by Bananas</h2>';
     $expected[] = '    ';
-    $expected[] = '';
-    $expected[] = '  <div class="content">';
-    $expected[] = '          ';
-    $expected[] = '      </div>';
-    $expected[] = '</div>';
+    $expected[] = '      ';
+    $expected[] = '  </div>';
     $expected[] = '';
     $expected_output = implode("\n", $expected);
     $this->assertEqual(drupal_render($output), $expected_output);
only in patch2:
unchanged:
--- a/core/modules/block/templates/block.html.twig
+++ b/core/modules/block/templates/block.html.twig
@@ -32,7 +32,6 @@
  *
  * @ingroup themeable
  */
- @todo Remove the div around content as per http://drupal.org/node/1972122.
 #}
 {%
   set classes = [
@@ -46,10 +45,7 @@
     <h2{{ title_attributes }}>{{ label }}</h2>
   {% endif %}
   {{ title_suffix }}
-
-  <div{{ content_attributes.addClass('content') }}>
-    {% block content %}
-      {{ content }}
-    {% endblock %}
-  </div>
+  {% block content %}
+    {{ content }}
+  {% endblock %}
 </div>
only in patch2:
unchanged:
--- a/core/modules/language/src/Tests/LanguageSwitchingTest.php
+++ b/core/modules/language/src/Tests/LanguageSwitchingTest.php
@@ -75,7 +75,7 @@ protected function doTestLanguageBlockAuthenticated($block_label) {
 
     // Assert that each list item and anchor element has the appropriate data-
     // attributes.
-    list($language_switcher) = $this->xpath('//div[@id=:id]/div[contains(@class, "content")]', array(':id' => 'block-test-language-block'));
+    list($language_switcher) = $this->xpath('//div[@id=:id]', array(':id' => 'block-test-language-block'));
     $list_items = array();
     $anchors = array();
     $labels = array();
@@ -125,7 +125,7 @@ protected function doTestLanguageBlockAnonymous($block_label) {
     $this->assertText($block_label, 'Language switcher block found.');
 
     // Assert that only the current language is marked as active.
-    list($language_switcher) = $this->xpath('//div[@id=:id]/div[contains(@class, "content")]', array(':id' => 'block-test-language-block'));
+    list($language_switcher) = $this->xpath('//div[@id=:id]', array(':id' => 'block-test-language-block'));
     $links = array(
       'active' => array(),
       'inactive' => array(),
only in patch2:
unchanged:
--- a/core/modules/search/search.module
+++ b/core/modules/search/search.module
@@ -115,7 +115,7 @@ function search_theme() {
 function search_preprocess_block(&$variables) {
   if ($variables['plugin_id'] == 'search_form_block') {
     $variables['attributes']['role'] = 'search';
-    $variables['content_attributes']['class'][] = 'container-inline';
+    $variables['attributes']['class'][] = 'container-inline';
   }
 }
 
only in patch2:
unchanged:
--- a/core/modules/views/src/Tests/Plugin/ExposedFormTest.php
+++ b/core/modules/views/src/Tests/Plugin/ExposedFormTest.php
@@ -143,7 +143,7 @@ public function testExposedBlock() {
     $this->drupalGet('test_exposed_block');
 
     // Test there is an exposed form in a block.
-    $xpath = $this->buildXPathQuery('//div[@id=:id]/div/form/@id', array(':id' => drupal_html_id('block-' . $block->id())));
+    $xpath = $this->buildXPathQuery('//div[@id=:id]/form/@id', array(':id' => drupal_html_id('block-' . $block->id())));
     $this->assertFieldByXpath($xpath, $this->getExpectedExposedFormId($view), 'Expected form found in views block.');
 
     // Test there is not an exposed form in the view page content area.