diff -u b/core/modules/block/block.module b/core/modules/block/block.module
--- b/core/modules/block/block.module
+++ b/core/modules/block/block.module
@@ -159,7 +159,7 @@
       else {
         $id = $theme . '_' . $default_theme_block_id;
       }
-      $block = $default_theme_block->createDuplicate($id, $theme);
+      $block = $default_theme_block->createDuplicateBlock($id, $theme);
       // If the region isn't supported by the theme, assign the block to the
       // theme's default region.
       if (!isset($regions[$block->getRegion()])) {
@@ -280,7 +280,7 @@
 function block_menu_delete(Menu $menu) {
   if (!$menu->isSyncing()) {
     foreach (Block::loadMultiple() as $block) {
-      if ($block->get('plugin') == 'system_menu_block:' . $menu->id()) {
+      if ($block->getPlugin() == 'system_menu_block:' . $menu->id()) {
         $block->delete();
       }
     }
diff -u b/core/modules/block/src/BlockInterface.php b/core/modules/block/src/BlockInterface.php
--- b/core/modules/block/src/BlockInterface.php
+++ b/core/modules/block/src/BlockInterface.php
@@ -143,2 +143,16 @@
 
+  /**
+   * Creates a duplicate of the block entity.
+   *
+   * @param string $new_id
+   *   (optional) The new ID on the duplicate block.
+   * @param string $new_theme
+   *   (optional) The theme on the duplicate block.
+   *
+   * @return static
+   *   A clone of $this with all identifiers unset, so saving it inserts a new
+   *   entity into the storage system.
+   */
+  public function createDuplicateBlock($new_id = NULL, $new_theme = NULL);
+
 }
diff -u b/core/modules/block/src/BlockListBuilder.php b/core/modules/block/src/BlockListBuilder.php
--- b/core/modules/block/src/BlockListBuilder.php
+++ b/core/modules/block/src/BlockListBuilder.php
@@ -402,7 +402,7 @@
       $entity_values = $form_state->getValue(array('blocks', $entity_id));
       $entity->setWeight($entity_values['weight']);
       $entity->setRegion($entity_values['region']);
-      if ($entity->get('region') == BlockInterface::BLOCK_REGION_NONE) {
+      if ($entity->getRegion() == BlockInterface::BLOCK_REGION_NONE) {
         $entity->disable();
       }
       else {
diff -u b/core/modules/block/src/Entity/Block.php b/core/modules/block/src/Entity/Block.php
--- b/core/modules/block/src/Entity/Block.php
+++ b/core/modules/block/src/Entity/Block.php
@@ -335,18 +335,9 @@
   }
 
   /**
-   * Creates a duplicate of the entity.
-   *
-   * @param string $new_id
-   *   (optional) The new ID on the duplicate block.
-   * @param string $new_theme
-   *   (optional) The theme on the duplicate block.
-   *
-   * @return static
-   *   A clone of $this with all identifiers unset, so saving it inserts a new
-   *   entity into the storage system.
+   * {@inheritdoc}
    */
-  public function createDuplicate($new_id = NULL, $new_theme = NULL) {
+  public function createDuplicateBlock($new_id = NULL, $new_theme = NULL) {
     $duplicate = parent::createDuplicate();
     if (!empty($new_id)) {
       $duplicate->id = $new_id;
only in patch2:
unchanged:
--- a/core/modules/block/src/BlockRepository.php
+++ b/core/modules/block/src/BlockRepository.php
@@ -78,7 +78,7 @@ public function getVisibleBlocksPerRegion(array $contexts) {
       /** @var \Drupal\block\BlockInterface $block */
       // Set the contexts on the block before checking access.
       if ($block->setContexts($contexts)->access('view')) {
-        $full[$block->get('region')][$block_id] = $block;
+        $full[$block->getRegion()][$block_id] = $block;
       }
     }
 
only in patch2:
unchanged:
--- a/core/modules/block/tests/src/Unit/BlockRepositoryTest.php
+++ b/core/modules/block/tests/src/Unit/BlockRepositoryTest.php
@@ -93,12 +93,8 @@ public function testGetVisibleBlocksPerRegion(array $blocks_config, array $expec
         ->method('access')
         ->will($this->returnValue($block_config[0]));
       $block->expects($block_config[0] ? $this->atLeastOnce() : $this->never())
-        ->method('get')
-        ->will($this->returnValueMap(array(
-          array('region', $block_config[1]),
-          array('weight', $block_config[2]),
-          array('status', TRUE),
-        )));
+        ->method('getRegion')
+        ->willReturn($block_config[1]);
       $blocks[$block_id] = $block;
     }
 
@@ -159,8 +155,7 @@ public function testGetVisibleBlocksPerRegionWithContext() {
       ->method('access')
       ->willReturn(TRUE);
     $block->expects($this->once())
-      ->method('get')
-      ->with('region')
+      ->method('getRegion')
       ->willReturn('top');
     $blocks['block_id'] = $block;
 
only in patch2:
unchanged:
--- a/core/modules/config_translation/src/Controller/ConfigTranslationBlockListBuilder.php
+++ b/core/modules/config_translation/src/Controller/ConfigTranslationBlockListBuilder.php
@@ -61,7 +61,7 @@ public function getFilterLabels() {
    * {@inheritdoc}
    */
   public function buildRow(EntityInterface $entity) {
-    $theme = $entity->get('theme');
+    $theme = $entity->getTheme();
     $plugin_definition = $entity->getPlugin()->getPluginDefinition();
 
     $row['label'] = array(