diff --git a/core/modules/block/block-admin-display-form.tpl.php b/core/modules/block/block-admin-display-form.tpl.php
index 0ce2b6b..1728273 100644
--- a/core/modules/block/block-admin-display-form.tpl.php
+++ b/core/modules/block/block-admin-display-form.tpl.php
@@ -25,15 +25,6 @@
  * @ingroup themeable
  */
 ?>
-<?php
-  // Add table javascript.
-  drupal_add_js('core/misc/tableheader.js');
-  drupal_add_js(drupal_get_path('module', 'block') . '/block.js');
-  foreach ($block_regions as $region => $title) {
-    drupal_add_tabledrag('blocks', 'match', 'sibling', 'block-region-select', 'block-region-' . $region, NULL, FALSE);
-    drupal_add_tabledrag('blocks', 'order', 'sibling', 'block-weight', 'block-weight-' . $region);
-  }
-?>
 <table id="blocks" class="sticky-enabled">
   <thead>
     <tr>
diff --git a/core/modules/block/block.admin.inc b/core/modules/block/block.admin.inc
index 2b3c2dd..e383e71 100644
--- a/core/modules/block/block.admin.inc
+++ b/core/modules/block/block.admin.inc
@@ -84,13 +84,22 @@ function block_admin_display_prepare_blocks($theme) {
  * @see block_admin_display_form_submit()
  */
 function block_admin_display_form($form, &$form_state, $blocks, $theme, $block_regions = NULL) {
-
-  $form['#attached']['css'] = array(drupal_get_path('module', 'block') . '/block.admin.css');
+  $path = drupal_get_path('module', 'block');
+  $form['#attached']['css'][] = $path . '/block.admin.css';
+  $form['#attached']['js'][] = 'core/misc/tableheader.js';
+  $form['#attached']['js'][] = $path . '/block.js';
 
   // Get a list of block regions if one was not provided.
   if (!isset($block_regions)) {
     $block_regions = system_region_list($theme, REGIONS_VISIBLE);
   }
+  // Add a last region for disabled blocks.
+  $block_regions_with_disabled = $block_regions + array(BLOCK_REGION_NONE => BLOCK_REGION_NONE);
+
+  foreach ($block_regions_with_disabled as $region => $title) {
+    $form['#attached']['drupal_add_tabledrag'][] = array('blocks', 'match', 'sibling', 'block-region-select', 'block-region-' . $region, NULL, FALSE);
+    $form['#attached']['drupal_add_tabledrag'][] = array('blocks', 'order', 'sibling', 'block-weight', 'block-weight-' . $region);
+  }
 
   // Weights range from -delta to +delta, so delta should be at least half
   // of the amount of blocks present. This makes sure all blocks in the same
@@ -104,8 +113,7 @@ function block_admin_display_form($form, &$form_state, $blocks, $theme, $block_r
   );
   $form['block_regions'] = array(
     '#type' => 'value',
-    // Add a last region for disabled blocks.
-    '#value' => $block_regions + array(BLOCK_REGION_NONE => BLOCK_REGION_NONE),
+    '#value' => $block_regions_with_disabled,
   );
   $form['blocks'] = array();
   $form['#tree'] = TRUE;