Decouple the block editor sidebar from the metabox hidden fields

admin/metabox/class-metabox.php

@@ -232,6 +232,10 @@ public function display_metabox( $identifier = null, $type = 'post_type' ) {
 	 * @return void
 	 */
 	public function add_meta_box() {
+		if ( $this->is_metabox_disabled_in_block_editor() ) {
+			return;
+		}
+
 		$post_types = WPSEO_Post_Type::get_accessible_post_types();
 		$post_types = array_filter( $post_types, [ $this, 'display_metabox' ] );
 
@@ -334,6 +338,32 @@ public function meta_box() {
 		$this->render_tabs();
 	}
 
+	/**
+	 * Returns whether the metabox hidden fields and $_POST-based save are disabled for the block editor.
+	 *
+	 * When this returns true the block editor uses the REST API meta path instead: all WPSEO post meta
+	 * fields are registered with show_in_rest, so core/editor carries and saves them automatically.
+	 *
+	 * Filter: 'wpseo_disable_metabox_in_block_editor'
+	 *
+	 * @return bool
+	 */
+	protected function is_metabox_disabled_in_block_editor() {
+		$screen = WP_Screen::get();
+		if ( ! $screen || ! $screen->is_block_editor() ) {
+			return false;
+		}
+
+		/**
+		 * Filter: 'wpseo_disable_metabox_in_block_editor' - Disables the Yoast metabox hidden fields
+		 * and the $_POST-based save hook in the block editor, so that post meta is saved via the
+		 * WordPress REST API instead (requires all relevant fields to have show_in_rest enabled).
+		 *
+		 * @param bool $disable Whether to disable the metabox. Default false.
+		 */
+		return (bool) apply_filters( 'wpseo_disable_metabox_in_block_editor', false );
+	}
+
 	/**
 	 * Renders the metabox hidden fields.
 	 *
@@ -700,6 +730,12 @@ public function save_postdata( $post_id ) {
 			return false;
 		}
 
+		// Bail when the REST API meta path is active: core/editor sends meta via REST,
+		// not via $_POST, so no nonce or hidden field values will be present.
+		if ( ( defined( 'REST_REQUEST' ) && REST_REQUEST ) && apply_filters( 'wpseo_disable_metabox_in_block_editor', false ) ) {
+			return;
+		}
+
 		if ( $post_id === null ) {
 			return false;
 		}
@@ -904,19 +940,20 @@ public function enqueue() {
 		$is_front_page    = $homepage_is_page && $page_on_front === (int) $post_id;
 
 		$script_data = [
-			'metabox'                    => $this->get_metabox_script_data(),
-			'isPost'                     => true,
-			'isBlockEditor'              => $is_block_editor,
-			'postId'                     => $post_id,
-			'postStatus'                 => get_post_status( $post_id ),
-			'postType'                   => get_post_type( $post_id ),
-			'isPage'                     => get_post_type( $post_id ) === 'page',
-			'usedKeywordsNonce'          => wp_create_nonce( 'wpseo-keyword-usage-and-post-types' ),
-			'analysis'                   => [
+			'metabox'                     => $this->get_metabox_script_data(),
+			'isPost'                      => true,
+			'isBlockEditor'               => $is_block_editor,
+			'disableMetaboxInBlockEditor' => $is_block_editor && (bool) apply_filters( 'wpseo_disable_metabox_in_block_editor', false ),
+			'postId'                      => $post_id,
+			'postStatus'                  => get_post_status( $post_id ),
+			'postType'                    => get_post_type( $post_id ),
+			'isPage'                      => get_post_type( $post_id ) === 'page',
+			'usedKeywordsNonce'           => wp_create_nonce( 'wpseo-keyword-usage-and-post-types' ),
+			'analysis'                    => [
 				'plugins' => $plugins_script_data,
 				'worker'  => $worker_script_data,
 			],
-			'isFrontPage'                => $is_front_page,
+			'isFrontPage'                 => $is_front_page,
 		];
 
 		/**

inc/class-wpseo-meta.php

@@ -123,18 +123,26 @@ class WPSEO_Meta {
 			'linkdex' => [
 				'type'          => 'hidden',
 				'default_value' => '0',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'content_score' => [
 				'type'          => 'hidden',
 				'default_value' => '0',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'inclusive_language_score' => [
 				'type'          => 'hidden',
 				'default_value' => '0',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'is_cornerstone' => [
 				'type'          => 'hidden',
 				'default_value' => 'false',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 		],
 		'advanced'        => [
@@ -146,6 +154,8 @@ class WPSEO_Meta {
 					'2' => '', // Index.
 					'1' => '', // No-index.
 				],
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'meta-robots-nofollow' => [
 				'type'          => 'hidden',
@@ -154,6 +164,8 @@ class WPSEO_Meta {
 					'0' => '', // Follow.
 					'1' => '', // No-follow.
 				],
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'meta-robots-adv'      => [
 				'type'          => 'hidden',
@@ -163,30 +175,42 @@ class WPSEO_Meta {
 					'noarchive'    => '',
 					'nosnippet'    => '',
 				],
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'bctitle'              => [
 				'type'          => 'hidden',
 				'default_value' => '',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'canonical'            => [
 				'type'          => 'hidden',
 				'default_value' => '',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 			'redirect'             => [
 				'type'          => 'url',
 				'default_value' => '',
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 		],
 		'social'          => [],
 		'schema'          => [
 			'schema_page_type'    => [
-				'type'    => 'hidden',
-				'options' => Schema_Types::PAGE_TYPES,
+				'type'         => 'hidden',
+				'options'      => Schema_Types::PAGE_TYPES,
+				'show_in_rest' => true,
+				'single'       => true,
 			],
 			'schema_article_type' => [
 				'type'          => 'hidden',
 				'hide_on_pages' => true,
 				'options'       => Schema_Types::ARTICLE_TYPES,
+				'show_in_rest'  => true,
+				'single'        => true,
 			],
 		],
 		/* Fields we should validate & save, but not show on any form. */
@@ -261,6 +285,8 @@ public static function init() {
 					self::$meta_fields['social'][ $network . '-' . $box ] = [
 						'type'          => $type,
 						'default_value' => '',
+						'show_in_rest'  => true,
+						'single'        => true,
 					];
 				}
 			}

packages/js/package.json

@@ -6,7 +6,7 @@
   "scripts": {
     "build": "cd ../.. && wp-scripts build --config config/webpack/webpack.config.js",
     "test": "jest",
-    "lint": "eslint . --max-warnings=40"
+    "lint": "eslint . --max-warnings=37"
   },
   "dependencies": {
     "@draft-js-plugins/mention": "^5.0.0",

packages/js/src/ai-content-planner/hooks/use-apply-outline.js

@@ -1,5 +1,6 @@
 import { useCallback } from "@wordpress/element";
 import { useDispatch, select } from "@wordpress/data";
+import { metaKeyTitle, metaKeyMetaDesc, metaKeyFocusKw } from "../../shared-admin/constants";
 import { buildBlocksFromOutline } from "../helpers/build-blocks-from-outline";
 import { CONTENT_PLANNER_STORE } from "../constants";
 
@@ -48,12 +49,9 @@ export const useApplyOutline = ( { editedOutlineRef } ) => {
 			title: metaOutline.title,
 			blocks: buildBlocksFromOutline( structure ),
 			meta: {
-				// eslint-disable-next-line camelcase
-				_yoast_wpseo_title: metaOutline.title,
-				// eslint-disable-next-line camelcase
-				_yoast_wpseo_metadesc: metaOutline.metaDescription,
-				// eslint-disable-next-line camelcase
-				_yoast_wpseo_focuskw: metaOutline.focusKeyphrase,
+				[ metaKeyTitle ]: metaOutline.title,
+				[ metaKeyMetaDesc ]: metaOutline.metaDescription,
+				[ metaKeyFocusKw ]: metaOutline.focusKeyphrase,
 			},
 		};
 		if ( metaOutline.category?.id && metaOutline.category.id !== -1 ) {

packages/js/src/ai-content-planner/hooks/use-yoast-meta-sync.js

@@ -1,39 +1,46 @@
 import { useDispatch, useSelect } from "@wordpress/data";
 import { useEffect } from "@wordpress/element";
+import { metaKeyTitle, metaKeyMetaDesc, metaKeyFocusKw, metaKeyIsCornerstone } from "../../shared-admin/constants";
 
 /**
  * Mirrors core/editor meta changes into yoast-seo/editor. Fires on every meta change,
  * including undo — which is intentional: undo should revert the Yoast fields too.
  * Direct sidebar edits (yoast-seo/editor only) will be overwritten if core/editor meta
  * changes afterwards — accepted trade-off for correct undo behaviour.
  *
+ * This hook is the core/editor → yoast-seo/editor direction. The reverse direction
+ * (yoast-seo/editor → core/editor) is handled by the Redux action creators in
+ * packages/js/src/redux/actions/ via the Fields helpers, which dispatch to core/editor
+ * when wpseoScriptData.disableMetaboxInBlockEditor is true.
+ *
  * @returns {void}
  */
 export function useYoastMetaSync() {
-	const { yoastTitle, yoastMetaDesc, yoastFocusKw, isPost, titleTemplate, descTemplate } = useSelect( select => {
+	const { yoastTitle, yoastMetaDesc, yoastFocusKw, yoastIsCornerstone, isPost, titleTemplate, descTemplate } = useSelect( select => {
 		const editor = select( "core/editor" );
 		const meta = editor.getEditedPostAttribute( "meta" );
 		const { title, description } = select( "yoast-seo/editor" ).getSnippetEditorTemplates();
 		return {
-			yoastTitle: meta?._yoast_wpseo_title,
-			yoastMetaDesc: meta?._yoast_wpseo_metadesc,
-			yoastFocusKw: meta?._yoast_wpseo_focuskw,
+			yoastTitle: meta?.[ metaKeyTitle ],
+			yoastMetaDesc: meta?.[ metaKeyMetaDesc ],
+			yoastFocusKw: meta?.[ metaKeyFocusKw ],
+			yoastIsCornerstone: meta?.[ metaKeyIsCornerstone ],
 			isPost: editor.getCurrentPostType() === "post",
 			titleTemplate: title,
 			descTemplate: description,
 		};
 	}, [] );
-	const { updateData, setFocusKeyword } = useDispatch( "yoast-seo/editor" );
+	const { updateData, setFocusKeyword, setCornerstoneContent } = useDispatch( "yoast-seo/editor" );
 
 	useEffect( () => {
 		// These meta keys are only registered for the 'post' subtype; bail on all other post types
 		// to avoid dispatching undefined values into yoast-seo/editor.
 		if ( ! isPost ) {
 			return;
 		}
-		// Only sync non-empty values. An empty string means no custom value has been saved, in
-		// which case the snippet editor should keep showing the SEO title template instead of
-		// being overwritten with an empty string.
+		// Only sync non-empty values. An empty string means no custom value has been saved,
+		// in which case the snippet editor should keep showing the SEO title
+		// template instead of being overwritten with an empty string.
 		const dataToSync = {
 			title: titleTemplate,
 			description: descTemplate,
@@ -46,5 +53,6 @@ export function useYoastMetaSync() {
 		}
 		updateData( dataToSync );
 		setFocusKeyword( yoastFocusKw || "" );
-	}, [ isPost, yoastTitle, yoastMetaDesc, yoastFocusKw, titleTemplate, descTemplate ] );
+		setCornerstoneContent( yoastIsCornerstone === "1" );
+	}, [ isPost, yoastTitle, yoastMetaDesc, yoastFocusKw, yoastIsCornerstone, titleTemplate, descTemplate ] );
 }