diff -r 3d4e9c994f10 -r a86126ab1dd4 wp/wp-includes/blocks/latest-comments.php
--- a/wp/wp-includes/blocks/latest-comments.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-includes/blocks/latest-comments.php	Tue Dec 15 13:49:49 2020 +0100
@@ -137,7 +137,7 @@
 	}
 	$classnames = esc_attr( $class );
 
-	$block_content = ! empty( $comments ) ? sprintf(
+	return ! empty( $comments ) ? sprintf(
 		'<ol class="%1$s">%2$s</ol>',
 		$classnames,
 		$list_items_markup
@@ -146,40 +146,18 @@
 		$classnames,
 		__( 'No comments to show.' )
 	);
-
-	return $block_content;
 }
 
-register_block_type(
-	'core/latest-comments',
-	array(
-		'attributes'      => array(
-			'align'          => array(
-				'type' => 'string',
-				'enum' => array( 'left', 'center', 'right', 'wide', 'full' ),
-			),
-			'className'      => array(
-				'type' => 'string',
-			),
-			'commentsToShow' => array(
-				'type'    => 'number',
-				'default' => 5,
-				'minimum' => 1,
-				'maximum' => 100,
-			),
-			'displayAvatar'  => array(
-				'type'    => 'boolean',
-				'default' => true,
-			),
-			'displayDate'    => array(
-				'type'    => 'boolean',
-				'default' => true,
-			),
-			'displayExcerpt' => array(
-				'type'    => 'boolean',
-				'default' => true,
-			),
-		),
-		'render_callback' => 'render_block_core_latest_comments',
-	)
-);
+/**
+ * Registers the `core/latest-comments` block.
+ */
+function register_block_core_latest_comments() {
+	register_block_type_from_metadata(
+		__DIR__ . '/latest-comments',
+		array(
+			'render_callback' => 'render_block_core_latest_comments',
+		)
+	);
+}
+
+add_action( 'init', 'register_block_core_latest_comments' );