diff --git a/wp-admin/edit-form-blocks.php b/wp-admin/edit-form-blocks.php
index 2e651d3f28..0ae82cb3a3 100644
--- a/wp-admin/edit-form-blocks.php
+++ b/wp-admin/edit-form-blocks.php
@@ -117,10 +117,10 @@ wp_add_inline_script(
 $meta_box_url = admin_url( 'post.php' );
 $meta_box_url = add_query_arg(
 	array(
-		'post'            => $post->ID,
-		'action'          => 'edit',
-		'meta-box-loader' => true,
-		'_wpnonce'        => wp_create_nonce( 'meta-box-loader' ),
+		'post'                  => $post->ID,
+		'action'                => 'edit',
+		'meta-box-loader'       => true,
+		'meta-box-loader-nonce' => wp_create_nonce( 'meta-box-loader' ),
 	),
 	$meta_box_url
 );
diff --git a/wp-admin/includes/post.php b/wp-admin/includes/post.php
index 0e19876e51..482d948bbc 100644
--- a/wp-admin/includes/post.php
+++ b/wp-admin/includes/post.php
@@ -2071,7 +2071,7 @@ function use_block_editor_for_post( $post ) {
 
 	// We're in the meta box loader, so don't use the block editor.
 	if ( isset( $_GET['meta-box-loader'] ) ) {
-		check_admin_referer( 'meta-box-loader' );
+		check_admin_referer( 'meta-box-loader', 'meta-box-loader-nonce' );
 		return false;
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index dd42a5b068..d9ac16c9c8 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.2-alpha-44937';
+$wp_version = '5.2-alpha-44938';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.