fix: detach layout classnames from inner elements

packages/block-library/src/comment-template/index.php

@@ -43,11 +43,18 @@ function block_core_comment_template_render_comments( $comments, $block ) {
 		 */
 		add_filter( 'render_block_context', $filter_block_context, 1 );
 
+		// Get an instance of the current Comment Template block.
+		$block_instance = $block->parsed_block;
+
+		// Set the block name to one that does not correspond to an existing registered block.
+		// This ensures that for the inner instances of the Comment Template block, we do not render any block supports.
+		$block_instance['blockName'] = 'core/null';
+
 		/*
 		 * We construct a new WP_Block instance from the parsed block so that
 		 * it'll receive any changes made by the `render_block_data` filter.
 		 */
-		$block_content = ( new WP_Block( $block->parsed_block ) )->render( array( 'dynamic' => false ) );
+		$block_content = ( new WP_Block( $block_instance ) )->render( array( 'dynamic' => false ) );
 
 		remove_filter( 'render_block_context', $filter_block_context, 1 );
 

phpunit/blocks/render-comment-template-test.php

@@ -159,7 +159,6 @@ public function test_inner_block_inserted_by_render_block_data_is_retained() {
 
 		$args = $render_block_callback->get_args();
 		$this->assertSame( 'core/comment-content', $args[0][2]->name );
-		$this->assertSame( 'core/comment-template', $args[1][2]->name );
 		$this->assertCount( 2, $args[1][2]->inner_blocks, "Inner block inserted by render_block_data filter wasn't retained." );
 		$this->assertInstanceOf(
 			'WP_Block',