.../block_content/src/Entity/BlockContent.php      |  5 +++++
 .../quickedit/src/Tests/QuickEditLoadingTest.php   | 24 +++++++++++++++++++---
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/core/modules/block_content/src/Entity/BlockContent.php b/core/modules/block_content/src/Entity/BlockContent.php
index 2d02dda..257043c 100644
--- a/core/modules/block_content/src/Entity/BlockContent.php
+++ b/core/modules/block_content/src/Entity/BlockContent.php
@@ -55,6 +55,11 @@
  *   field_ui_base_route = "entity.block_content_type.edit_form",
  *   render_cache = FALSE,
  * )
+ *
+ * Note that render caching of block_content entities is disabled because they
+ * are always rendered as blocks, and blocks already have their own render
+ * caching.
+ * See https://www.drupal.org/node/2284917#comment-9132521 for more information.
  */
 class BlockContent extends ContentEntityBase implements BlockContentInterface {
 
diff --git a/core/modules/quickedit/src/Tests/QuickEditLoadingTest.php b/core/modules/quickedit/src/Tests/QuickEditLoadingTest.php
index 682f2cd..5865655 100644
--- a/core/modules/quickedit/src/Tests/QuickEditLoadingTest.php
+++ b/core/modules/quickedit/src/Tests/QuickEditLoadingTest.php
@@ -8,11 +8,10 @@
 namespace Drupal\quickedit\Tests;
 
 use Drupal\Component\Serialization\Json;
-use Drupal\simpletest\WebTestBase;
-use Drupal\quickedit\Ajax\MetadataCommand;
-use Drupal\Core\Ajax\AppendCommand;
 use Drupal\Component\Utility\Unicode;
+use Drupal\block_content\Entity\BlockContent;
 use Drupal\node\Entity\Node;
+use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests loading of in-place editing functionality and lazy loading of its
@@ -493,4 +492,23 @@ public function testConcurrentEdit() {
     }
   }
 
+  /**
+   * Tests that Quick Edit's data- attributes are present for content blocks.
+   */
+  public function testContentBlock() {
+    \Drupal::service('module_installer')->install(array('block_content'));
+
+    // Create and place a content_block block.
+    $block = BlockContent::create([
+      'info' => $this->randomMachineName(),
+      'type' => 'basic',
+      'langcode' => 'en',
+    ]);
+    $block->save();
+    $this->drupalPlaceBlock('block_content:' . $block->uuid());
+
+    // Check that the data- attribute is present.
+    $this->drupalGet('');
+    $this->assertRaw('data-quickedit-entity-id="block_content/1"');
+  }
 }