Framework: Enqueue assets for rendered blocks only

lib/class-wp-block.php

@@ -206,6 +206,14 @@ public function render( $options = array() ) {
 			$post          = $global_post;
 		}
 
+		if ( ! empty( $this->block_type->script ) ) {
+			wp_enqueue_script( $this->block_type->script );
+		}
+
+		if ( ! empty( $this->block_type->style ) ) {
+			wp_enqueue_style( $this->block_type->style );
+		}
+
 		/** This filter is documented in src/wp-includes/blocks.php */
 		return apply_filters( 'render_block', $block_content, $this->parsed_block );
 	}

lib/compat.php

@@ -230,3 +230,12 @@ function gutenberg_render_block_with_assigned_block_context( $pre_render, $parse
 	return $block->render();
 }
 add_filter( 'pre_render_block', 'gutenberg_render_block_with_assigned_block_context', 9, 2 );
+
+/**
+ * Avoid enqueueing block assets of all registered blocks for all posts, instead
+ * deferring to block render mechanics to enqueue scripts, thereby ensuring only
+ * blocks of the content have their assets enqueued.
+ *
+ * @see WP_Block::render
+ */
+remove_action( 'enqueue_block_assets', 'wp_enqueue_registered_block_scripts_and_styles' );