Site Editor: preload settings requests

backport-changelog/6.8/7687.md

@@ -0,0 +1,3 @@
+https://github.com/WordPress/wordpress-develop/pull/7687
+
+* https://github.com/WordPress/gutenberg/pull/66488

lib/compat/wordpress-6.8/preload.php

@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * Preload necessary resources for the editors.
+ *
+ * @param array                   $paths   REST API paths to preload.
+ * @param WP_Block_Editor_Context $context Current block editor context
+ *
+ * @return array Filtered preload paths.
+ */
+function gutenberg_block_editor_preload_paths_6_8( $paths, $context ) {
+	if ( 'core/edit-site' === $context->name ) {
+		// Core already preloads both of these for `core/edit-post`.
+		$paths[] = '/wp/v2/settings';
+		$paths[] = array( '/wp/v2/settings', 'OPTIONS' );
+		$paths[] = '/?_fields=' . implode(
+			',',
+			// @see packages/core-data/src/entities.js
+			array(
+				'description',
+				'gmt_offset',
+				'home',
+				'name',
+				'site_icon',
+				'site_icon_url',
+				'site_logo',
+				'timezone_string',
+				'url',
+			)
+		);
+	}
+	return $paths;
+}
+add_filter( 'block_editor_rest_api_preload_paths', 'gutenberg_block_editor_preload_paths_6_8', 10, 2 );

lib/load.php

@@ -116,6 +116,9 @@ function gutenberg_is_experiment_enabled( $name ) {
 require __DIR__ . '/compat/wordpress-6.7/compat.php';
 require __DIR__ . '/compat/wordpress-6.7/post-formats.php';
 
+// WordPress 6.8 compat.
+require __DIR__ . '/compat/wordpress-6.8/preload.php';
+
 // Experimental features.
 require __DIR__ . '/experimental/block-editor-settings-mobile.php';
 require __DIR__ . '/experimental/blocks.php';

packages/core-data/src/entities.js

@@ -20,6 +20,8 @@ export const rootEntitiesConfig = [
 		name: '__unstableBase',
 		baseURL: '/',
 		baseURLParams: {
+			// Please also change the preload path when changing this.
+			// @see lib/compat/wordpress-6.8/preload.php
 			_fields: [
 				'description',
 				'gmt_offset',