From 816e55cfbc7fa2d8b4be291eeb5315ddf374c0a6 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Fri, 16 Jan 2026 08:09:30 +1100
Subject: [PATCH 01/30] Being adding user info

---
 .../lib/util.js                               |  1 -
 packages/sync/package.json                    |  1 +
 .../sync/src/awareness/awareness-manager.ts   | 24 +++++++-
 .../sync/src/awareness/awareness-state.ts     | 55 +++++++++++--------
 .../sync/src/awareness/awareness-types.ts     | 29 +++++++++-
 .../awareness/post-editor-awareness-state.ts  | 14 ++++-
 packages/sync/src/index.ts                    |  3 +
 packages/sync/src/utils.ts                    | 47 ++++++++++++++++
 8 files changed, 145 insertions(+), 29 deletions(-)

diff --git a/packages/dependency-extraction-webpack-plugin/lib/util.js b/packages/dependency-extraction-webpack-plugin/lib/util.js
index 5a5d88b8006ff6..ce420116404a29 100644
--- a/packages/dependency-extraction-webpack-plugin/lib/util.js
+++ b/packages/dependency-extraction-webpack-plugin/lib/util.js
@@ -5,7 +5,6 @@ const BUNDLED_PACKAGES = [
 	'@wordpress/dataviews/wp',
 	'@wordpress/icons',
 	'@wordpress/interface',
-	'@wordpress/sync',
 	'@wordpress/undo-manager',
 	'@wordpress/upload-media',
 	'@wordpress/fields',
diff --git a/packages/sync/package.json b/packages/sync/package.json
index 4d6500f1d80098..92c13425be0673 100644
--- a/packages/sync/package.json
+++ b/packages/sync/package.json
@@ -30,6 +30,7 @@
 		"*.md"
 	],
 	"main": "build/index.cjs",
+	"wpScript": true,
 	"module": "build-module/index.mjs",
 	"exports": {
 		".": {
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 6e814ca9dd9429..7c5e56778f59d6 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -3,12 +3,19 @@
  */
 import type * as Y from 'yjs';
 
+/**
+ * WordPress dependencies
+ */
+import { select } from '@wordpress/data';
+
 /**
  * Internal dependencies
  */
 import type { ObjectID, ObjectType } from '../types';
 import type { AwarenessState } from './awareness-state';
 import { PostEditorAwarenessState } from './post-editor-awareness-state';
+import { UserInfo, WordPressUserInfo } from './awareness-types';
+import { getBrowserName } from '../utils';
 
 const awarenessInstances: Map< string, AwarenessState > = new Map();
 
@@ -26,6 +33,14 @@ function getAwarenessInstance(
 	return awarenessInstances.get( getAwarenessId( objectType, objectId ) );
 }
 
+function getUserInfo( wpUser: WordPressUserInfo ): UserInfo {
+	return {
+		...wpUser,
+		browserType: getBrowserName(),
+		enteredAt: Date.now(),
+	};
+}
+
 /**
  * Get the post editor awareness instance for the given post ID and post type.
  * @param postId   Post ID.
@@ -61,7 +76,14 @@ export async function createAwareness(
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
-		awareness.setUp();
+
+		const currentUser = select( 'core/data' ).getCurrentUser();
+
+		console.log( 'currentUser', currentUser );
+		const userInfo = getUserInfo( currentUser );
+		console.log( 'userInfo', userInfo );
+
+		awareness.setUp( userInfo );
 		awarenessInstances.set(
 			getAwarenessId( objectType, objectId ),
 			awareness
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 899d8091a0d4b3..1faa887426a40e 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -3,6 +3,7 @@
  */
 import {
 	TypedAwareness,
+	UserInfo,
 	type BaseState,
 	type EnhancedState,
 	type EqualityFieldCheck,
@@ -150,7 +151,9 @@ export abstract class AwarenessState<
 	/**
 	 * Set up.
 	 */
-	public setUp(): void {
+	public setUp( userInfo: UserInfo): void {
+		this.setLocalStateField( 'userInfo', userInfo );
+
 		this.on(
 			'change',
 			( { added, removed, updated }: AwarenessStateChange ) => {
@@ -228,27 +231,35 @@ export abstract class AwarenessState<
 		] );
 
 		const updatedStates = new Map< number, EnhancedState< State > >(
-			[ ...this.disconnectedUsers, ...states.keys() ].map(
-				( clientId ) => {
-					const rawState: State = this.seenStates.get( clientId )!;
-
-					const isConnected =
-						! this.disconnectedUsers.has( clientId );
-					const isMe = clientId === this.clientID;
-					const myState: Partial< State > = isMe
-						? this.myThrottledState
-						: {};
-					const state: EnhancedState< State > = {
-						...rawState,
-						...myState,
-						clientId,
-						isConnected,
-						isMe,
-					};
-
-					return [ clientId, state ];
-				}
-			)
+			[ ...this.disconnectedUsers, ...states.keys() ]
+				.filter( clientId => {
+					// Exclude any users without `userInfo`.
+					// This can happen from the Yjs inspector, which joins the awareness
+					// state without providing user data.
+					return Boolean( this.seenStates.get( clientId )?.userInfo );
+				} )
+				.map(
+					( clientId ) => {
+						// The filter above ensures that seenStates has the clientId.
+						const rawState: State = this.seenStates.get( clientId )!;
+
+						const isConnected =
+							! this.disconnectedUsers.has( clientId );
+						const isMe = clientId === this.clientID;
+						const myState: Partial< State > = isMe
+							? this.myThrottledState
+							: {};
+						const state: EnhancedState< State > = {
+							...rawState,
+							...myState,
+							clientId,
+							isConnected,
+							isMe,
+						};
+
+						return [ clientId, state ];
+					}
+				)
 		);
 
 		if ( ! forceUpdate ) {
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index c786f1d0c54d86..0d373a606c6ebf 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -37,14 +37,37 @@ export class TypedAwareness< State extends BaseState > extends Awareness {
 	}
 }
 
+/**
+ * This base user info is a subset of the User interface from @wordpress/core-data.
+ *
+ * In order to avoid circular dependencies, we define it here instead of importing
+ * the User interface from @wordpress/core-data.
+ *
+ * The avatarUrl is an additional field that is not part of the User interface.
+ */
+export interface WordPressUserInfo {
+	id: number;
+	name: string;
+	avatarUrl?: string;
+}
+
+/**
+ * The user info interface extends the base user info with additional fields used for presence
+ * indicators.
+ */
+export interface UserInfo extends WordPressUserInfo {
+	browserType: string;
+	enteredAt: number;
+}
+
 /**
  * This base state represents the presence of the user. We expect it to be
  * extended to include additional state describing the user's current activity.
  * This state must be serializable and compact.
- *
- * TODO: Add in the user information.
  */
-export interface BaseState {}
+export interface BaseState {
+	userInfo: UserInfo;
+}
 
 /**
  * An enhanced state includes additional metadata about the user's connection
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 2b1c3518a8aa6d..0a36bbc9af569c 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -1,8 +1,18 @@
-import type { PostEditorState } from './awareness-types';
+/**
+ * Internal dependencies
+ */
+import type { PostEditorState, UserInfo } from './awareness-types';
 import { AwarenessState } from './awareness-state';
+import { areUserInfosEqual } from '../utils';
 
 export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
-	protected equalityFieldChecks = {};
+	protected equalityFieldChecks = {
+		userInfo: areUserInfosEqual,
+	};
+
+	public setUp( userInfo: UserInfo ): void {
+		super.setUp( userInfo );
+	}
 
 	// TODO: Add in subscription for user selection changes.
 }
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 1aa27a30724100..d17ec2dbc2fa18 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -25,3 +25,6 @@ export {
 } from './config';
 export { createSyncManager } from './manager';
 export type * from './types';
+export {
+	setConnectionStatus,
+} from './awareness/awareness-manager';
diff --git a/packages/sync/src/utils.ts b/packages/sync/src/utils.ts
index fcd77dc6db2661..7b4d6f7e61de9e 100644
--- a/packages/sync/src/utils.ts
+++ b/packages/sync/src/utils.ts
@@ -14,6 +14,7 @@ import {
 	CRDT_STATE_VERSION_KEY,
 } from './config';
 import type { CRDTDoc } from './types';
+import type { UserInfo } from './awareness/awareness-types';
 
 // An object representation of CRDT document metadata.
 type DocumentMeta = Record< string, DocumentMetaValue >;
@@ -105,3 +106,49 @@ export function areMapsEqual< Key, Value >(
 
 	return true;
 }
+
+/**
+ * Compare two user infos for equality.
+ * @param userInfo1 - The first user info to compare.
+ * @param userInfo2 - The second user info to compare.
+ * @returns True if the user infos are equal, false otherwise.
+ */
+export function areUserInfosEqual( userInfo1?: UserInfo, userInfo2?: UserInfo ): boolean {
+	if ( ! userInfo1 || ! userInfo2 ) {
+		return userInfo1 === userInfo2;
+	}
+
+	if ( Object.keys( userInfo1 ).length !== Object.keys( userInfo2 ).length ) {
+		return false;
+	}
+
+	return Object.entries( userInfo1 ).every( ( [ key, value ] ) => {
+		// Update this function with any non-primitive fields added to UserInfo.
+		return value === userInfo2[ key as keyof UserInfo ];
+	} );
+}
+
+/**
+ * Get the browser name from the user agent.
+ * @returns The browser name.
+ */
+export function getBrowserName(): string {
+	const userAgent = window.navigator.userAgent;
+	let browserName = 'Unknown';
+
+	if ( userAgent.includes( 'Firefox' ) ) {
+		browserName = 'Firefox';
+	} else if ( userAgent.includes( 'Edg' ) ) {
+		browserName = 'Microsoft Edge';
+	} else if ( userAgent.includes( 'Chrome' ) && ! userAgent.includes( 'Edg' ) ) {
+		browserName = 'Chrome';
+	} else if ( userAgent.includes( 'Safari' ) && ! userAgent.includes( 'Chrome' ) ) {
+		browserName = 'Safari';
+	} else if ( userAgent.includes( 'MSIE' ) || userAgent.includes( 'Trident' ) ) {
+		browserName = 'Internet Explorer';
+	} else if ( userAgent.includes( 'Opera' ) || userAgent.includes( 'OPR' ) ) {
+		browserName = 'Opera';
+	}
+
+	return browserName;
+}

From f81ed74b9b1ad76a4c49ce065f428b37e1e51bd0 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Fri, 16 Jan 2026 11:50:21 +1100
Subject: [PATCH 02/30] Got the user fetch working

---
 packages/core-data/src/resolvers.js           |  3 ++
 .../sync/src/awareness/awareness-manager.ts   | 22 +++------
 .../sync/src/awareness/awareness-state.ts     | 49 +++++++++----------
 .../sync/src/awareness/awareness-types.ts     |  2 +-
 packages/sync/src/index.ts                    |  4 +-
 packages/sync/src/manager.ts                  | 20 +++++---
 packages/sync/src/test/manager.ts             | 15 ++++++
 packages/sync/src/types.ts                    |  2 +
 packages/sync/src/utils.ts                    | 24 ++++++---
 9 files changed, 85 insertions(+), 56 deletions(-)

diff --git a/packages/core-data/src/resolvers.js b/packages/core-data/src/resolvers.js
index 39ed5d95b281fa..9787d1e84a4623 100644
--- a/packages/core-data/src/resolvers.js
+++ b/packages/core-data/src/resolvers.js
@@ -223,6 +223,9 @@ export const getEntityRecord =
 									key
 								);
 							},
+							// Get the current user.
+							getCurrentUser: async () =>
+								await resolveSelect.getCurrentUser(),
 						}
 					);
 				}
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 7c5e56778f59d6..33975c596adaf1 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -3,18 +3,13 @@
  */
 import type * as Y from 'yjs';
 
-/**
- * WordPress dependencies
- */
-import { select } from '@wordpress/data';
-
 /**
  * Internal dependencies
  */
 import type { ObjectID, ObjectType } from '../types';
 import type { AwarenessState } from './awareness-state';
 import { PostEditorAwarenessState } from './post-editor-awareness-state';
-import { UserInfo, WordPressUserInfo } from './awareness-types';
+import type { UserInfo, WordPressUserInfo } from './awareness-types';
 import { getBrowserName } from '../utils';
 
 const awarenessInstances: Map< string, AwarenessState > = new Map();
@@ -64,24 +59,21 @@ export function getPostEditorAwareness(
 
 /**
  * Create an awareness instance for the given object type and object ID.
- * @param objectType Object type.
- * @param objectId   Object ID.
- * @param ydoc       Yjs document.
+ * @param objectType  Object type.
+ * @param objectId    Object ID.
+ * @param ydoc        Yjs document.
+ * @param currentUser Current user.
  * @return Awareness instance.
  */
 export async function createAwareness(
 	objectType: ObjectType,
 	objectId: ObjectID | null,
-	ydoc: Y.Doc
+	ydoc: Y.Doc,
+	currentUser: WordPressUserInfo
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
-
-		const currentUser = select( 'core/data' ).getCurrentUser();
-
-		console.log( 'currentUser', currentUser );
 		const userInfo = getUserInfo( currentUser );
-		console.log( 'userInfo', userInfo );
 
 		awareness.setUp( userInfo );
 		awarenessInstances.set(
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 1faa887426a40e..95ab2c8a6bb1f6 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -1,9 +1,9 @@
 /**
  * Internal dependencies
  */
+import type { UserInfo } from './awareness-types';
 import {
 	TypedAwareness,
-	UserInfo,
 	type BaseState,
 	type EnhancedState,
 	type EqualityFieldCheck,
@@ -150,8 +150,9 @@ export abstract class AwarenessState<
 
 	/**
 	 * Set up.
+	 * @param userInfo
 	 */
-	public setUp( userInfo: UserInfo): void {
+	public setUp( userInfo: UserInfo ): void {
 		this.setLocalStateField( 'userInfo', userInfo );
 
 		this.on(
@@ -232,34 +233,32 @@ export abstract class AwarenessState<
 
 		const updatedStates = new Map< number, EnhancedState< State > >(
 			[ ...this.disconnectedUsers, ...states.keys() ]
-				.filter( clientId => {
+				.filter( ( clientId ) => {
 					// Exclude any users without `userInfo`.
 					// This can happen from the Yjs inspector, which joins the awareness
 					// state without providing user data.
 					return Boolean( this.seenStates.get( clientId )?.userInfo );
 				} )
-				.map(
-					( clientId ) => {
-						// The filter above ensures that seenStates has the clientId.
-						const rawState: State = this.seenStates.get( clientId )!;
-
-						const isConnected =
-							! this.disconnectedUsers.has( clientId );
-						const isMe = clientId === this.clientID;
-						const myState: Partial< State > = isMe
-							? this.myThrottledState
-							: {};
-						const state: EnhancedState< State > = {
-							...rawState,
-							...myState,
-							clientId,
-							isConnected,
-							isMe,
-						};
-
-						return [ clientId, state ];
-					}
-				)
+				.map( ( clientId ) => {
+					// The filter above ensures that seenStates has the clientId.
+					const rawState: State = this.seenStates.get( clientId )!;
+
+					const isConnected =
+						! this.disconnectedUsers.has( clientId );
+					const isMe = clientId === this.clientID;
+					const myState: Partial< State > = isMe
+						? this.myThrottledState
+						: {};
+					const state: EnhancedState< State > = {
+						...rawState,
+						...myState,
+						clientId,
+						isConnected,
+						isMe,
+					};
+
+					return [ clientId, state ];
+				} )
 		);
 
 		if ( ! forceUpdate ) {
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index 0d373a606c6ebf..5baa57860955a4 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -48,7 +48,7 @@ export class TypedAwareness< State extends BaseState > extends Awareness {
 export interface WordPressUserInfo {
 	id: number;
 	name: string;
-	avatarUrl?: string;
+	avatar_urls: Record< string, string >;
 }
 
 /**
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index d17ec2dbc2fa18..e84771bd6e8564 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -25,6 +25,4 @@ export {
 } from './config';
 export { createSyncManager } from './manager';
 export type * from './types';
-export {
-	setConnectionStatus,
-} from './awareness/awareness-manager';
+export { setConnectionStatus } from './awareness/awareness-manager';
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index 0293b096bf505f..e2e1a743621459 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -78,11 +78,11 @@ export function createSyncManager(): SyncManager {
 	/**
 	 * Load an entity for syncing and manage its lifecycle.
 	 *
-	 * @param {SyncConfig}     syncConfig Sync configuration for the object type.
-	 * @param {ObjectType}     objectType Object type.
-	 * @param {ObjectID}       objectId   Object ID.
-	 * @param {ObjectData}     record     Entity record representing this object type.
-	 * @param {RecordHandlers} handlers   Handlers for updating and fetching the record.
+	 * @param {SyncConfig}        syncConfig  Sync configuration for the object type.
+	 * @param {ObjectType}        objectType  Object type.
+	 * @param {ObjectID}          objectId    Object ID.
+	 * @param {ObjectData}        record      Entity record representing this object type.
+	 * @param {RecordHandlers}    handlers    Handlers for updating and fetching the record.
 	 */
 	async function loadEntity(
 		syncConfig: SyncConfig,
@@ -147,8 +147,16 @@ export function createSyncManager(): SyncManager {
 
 		entityStates.set( entityId, entityState );
 
+		// Get the current user from the handlers.
+		const currentUser = await handlers.getCurrentUser();
+
 		// Create awareness for the given entity and its Yjs document.
-		const awareness = await createAwareness( objectType, objectId, ydoc );
+		const awareness = await createAwareness(
+			objectType,
+			objectId,
+			ydoc,
+			currentUser
+		);
 
 		// Create providers for the given entity and its Yjs document.
 		const providerResults = await Promise.all(
diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index 3853caedac1603..9f48bf3aab62ee 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -31,6 +31,7 @@ import type {
 	RecordHandlers,
 	SyncConfig,
 } from '../types';
+import type { WordPressUserInfo } from '../awareness/awareness-types';
 
 // Mock dependencies.
 jest.mock( '../providers', () => ( {
@@ -43,6 +44,7 @@ describe( 'SyncManager', () => {
 	let mockProviderCreator: jest.Mock< ProviderCreator >;
 	let mockProviderResult: ProviderCreatorResult;
 	let mockRecord: ObjectData;
+	let mockCurrentUser: WordPressUserInfo;
 	let mockSyncConfig: jest.MockedObject< SyncConfig >;
 
 	beforeEach( () => {
@@ -54,6 +56,16 @@ describe( 'SyncManager', () => {
 			title: 'Test Post',
 		};
 
+		mockCurrentUser = {
+			id: 1,
+			name: 'Test User',
+			avatar_urls: {
+				'24': 'https://example.com/avatar.jpg',
+				'48': 'https://example.com/avatar-48.jpg',
+				'96': 'https://example.com/avatar-96.jpg',
+			},
+		};
+
 		mockProviderResult = {
 			destroy: jest.fn(),
 		};
@@ -89,6 +101,9 @@ describe( 'SyncManager', () => {
 				Promise.resolve( mockRecord )
 			),
 			saveRecord: jest.fn( async () => Promise.resolve() ),
+			getCurrentUser: jest.fn( async () =>
+				Promise.resolve( mockCurrentUser )
+			),
 		};
 	} );
 
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index c7e39b0e2773bb..9d6525b8e83ba9 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -13,6 +13,7 @@ import type { Awareness } from 'y-protocols/awareness';
  * Internal dependencies
  */
 import type { WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE } from './config';
+import type { WordPressUserInfo } from './awareness/awareness-types';
 
 /* globalThis */
 declare global {
@@ -64,6 +65,7 @@ export interface RecordHandlers {
 	editRecord: ( data: Partial< ObjectData > ) => void;
 	getEditedRecord: () => Promise< ObjectData >;
 	saveRecord: () => Promise< void >;
+	getCurrentUser: () => Promise< WordPressUserInfo >;
 }
 
 export interface SyncConfig {
diff --git a/packages/sync/src/utils.ts b/packages/sync/src/utils.ts
index 7b4d6f7e61de9e..3ae24d1e5a344a 100644
--- a/packages/sync/src/utils.ts
+++ b/packages/sync/src/utils.ts
@@ -111,9 +111,12 @@ export function areMapsEqual< Key, Value >(
  * Compare two user infos for equality.
  * @param userInfo1 - The first user info to compare.
  * @param userInfo2 - The second user info to compare.
- * @returns True if the user infos are equal, false otherwise.
+ * @return True if the user infos are equal, false otherwise.
  */
-export function areUserInfosEqual( userInfo1?: UserInfo, userInfo2?: UserInfo ): boolean {
+export function areUserInfosEqual(
+	userInfo1?: UserInfo,
+	userInfo2?: UserInfo
+): boolean {
 	if ( ! userInfo1 || ! userInfo2 ) {
 		return userInfo1 === userInfo2;
 	}
@@ -130,7 +133,7 @@ export function areUserInfosEqual( userInfo1?: UserInfo, userInfo2?: UserInfo ):
 
 /**
  * Get the browser name from the user agent.
- * @returns The browser name.
+ * @return The browser name.
  */
 export function getBrowserName(): string {
 	const userAgent = window.navigator.userAgent;
@@ -140,11 +143,20 @@ export function getBrowserName(): string {
 		browserName = 'Firefox';
 	} else if ( userAgent.includes( 'Edg' ) ) {
 		browserName = 'Microsoft Edge';
-	} else if ( userAgent.includes( 'Chrome' ) && ! userAgent.includes( 'Edg' ) ) {
+	} else if (
+		userAgent.includes( 'Chrome' ) &&
+		! userAgent.includes( 'Edg' )
+	) {
 		browserName = 'Chrome';
-	} else if ( userAgent.includes( 'Safari' ) && ! userAgent.includes( 'Chrome' ) ) {
+	} else if (
+		userAgent.includes( 'Safari' ) &&
+		! userAgent.includes( 'Chrome' )
+	) {
 		browserName = 'Safari';
-	} else if ( userAgent.includes( 'MSIE' ) || userAgent.includes( 'Trident' ) ) {
+	} else if (
+		userAgent.includes( 'MSIE' ) ||
+		userAgent.includes( 'Trident' )
+	) {
 		browserName = 'Internet Explorer';
 	} else if ( userAgent.includes( 'Opera' ) || userAgent.includes( 'OPR' ) ) {
 		browserName = 'Opera';

From 6e3eb809cb0f9a4a2b5f0e464128a3eb607d380c Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Fri, 16 Jan 2026 15:02:10 +1100
Subject: [PATCH 03/30] Added in some test logging

---
 .../sync/src/awareness/awareness-manager.ts   |  21 ++-
 .../sync/src/awareness/awareness-types.ts     |   2 +
 .../awareness/post-editor-awareness-state.ts  |  17 ++-
 packages/sync/src/local-storage.ts            |  51 +++++++
 packages/sync/src/manager.ts                  |  10 +-
 packages/sync/src/test/manager.ts             |   1 +
 packages/sync/src/user-utils.ts               | 139 ++++++++++++++++++
 packages/sync/src/utils.ts                    |  58 --------
 8 files changed, 230 insertions(+), 69 deletions(-)
 create mode 100644 packages/sync/src/local-storage.ts
 create mode 100644 packages/sync/src/user-utils.ts

diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 33975c596adaf1..37fd2de05abfe3 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -10,7 +10,7 @@ import type { ObjectID, ObjectType } from '../types';
 import type { AwarenessState } from './awareness-state';
 import { PostEditorAwarenessState } from './post-editor-awareness-state';
 import type { UserInfo, WordPressUserInfo } from './awareness-types';
-import { getBrowserName } from '../utils';
+import { getBrowserName, getNewUserColor } from '../user-utils';
 
 const awarenessInstances: Map< string, AwarenessState > = new Map();
 
@@ -28,10 +28,23 @@ function getAwarenessInstance(
 	return awarenessInstances.get( getAwarenessId( objectType, objectId ) );
 }
 
-function getUserInfo( wpUser: WordPressUserInfo ): UserInfo {
+function getUserInfo(
+	awareness: AwarenessState,
+	wpUser: WordPressUserInfo
+): UserInfo {
+	const states = awareness.getStates();
+	const otherUserColors = Array.from( states.entries() )
+		.filter(
+			( [ clientId, state ] ) =>
+				state.userInfo && clientId !== awareness.clientID
+		)
+		.map( ( [ _clientId, state ] ) => state.userInfo.color )
+		.filter( Boolean );
+
 	return {
 		...wpUser,
 		browserType: getBrowserName(),
+		color: getNewUserColor( otherUserColors ),
 		enteredAt: Date.now(),
 	};
 }
@@ -73,8 +86,7 @@ export async function createAwareness(
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
-		const userInfo = getUserInfo( currentUser );
-
+		const userInfo = getUserInfo( awareness, currentUser );
 		awareness.setUp( userInfo );
 		awarenessInstances.set(
 			getAwarenessId( objectType, objectId ),
@@ -83,7 +95,6 @@ export async function createAwareness(
 
 		return awareness;
 	}
-
 	return undefined;
 }
 
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index 5baa57860955a4..bc4e5eb93364ff 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -48,6 +48,7 @@ export class TypedAwareness< State extends BaseState > extends Awareness {
 export interface WordPressUserInfo {
 	id: number;
 	name: string;
+	slug: string;
 	avatar_urls: Record< string, string >;
 }
 
@@ -57,6 +58,7 @@ export interface WordPressUserInfo {
  */
 export interface UserInfo extends WordPressUserInfo {
 	browserType: string;
+	color: string;
 	enteredAt: number;
 }
 
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 0a36bbc9af569c..9ebae5b554e6fd 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -1,9 +1,14 @@
+/**
+ * External dependencies
+ */
+import * as Y from 'yjs';
 /**
  * Internal dependencies
  */
 import type { PostEditorState, UserInfo } from './awareness-types';
 import { AwarenessState } from './awareness-state';
-import { areUserInfosEqual } from '../utils';
+import { areUserInfosEqual } from '../user-utils';
+import { CRDT_RECORD_MAP_KEY } from '../config';
 
 export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
 	protected equalityFieldChecks = {
@@ -12,6 +17,16 @@ export class PostEditorAwarenessState extends AwarenessState< PostEditorState >
 
 	public setUp( userInfo: UserInfo ): void {
 		super.setUp( userInfo );
+
+		this.subscribeToCRDTChanges();
+	}
+
+	private subscribeToCRDTChanges(): void {
+		const recordMap = this.doc.getMap( CRDT_RECORD_MAP_KEY );
+
+		recordMap.observeDeep( ( changes ) => {
+			console.log( changes );
+		} );
 	}
 
 	// TODO: Add in subscription for user selection changes.
diff --git a/packages/sync/src/local-storage.ts b/packages/sync/src/local-storage.ts
new file mode 100644
index 00000000000000..b249d1306183b1
--- /dev/null
+++ b/packages/sync/src/local-storage.ts
@@ -0,0 +1,51 @@
+/**
+ * Load data from localStorage with error handling
+ * @param key          - The localStorage key to read from
+ * @param defaultValue - The default value to return if loading fails or key doesn't exist
+ * @return The parsed data from localStorage or the default value
+ */
+export const loadFromLocalStorage = < T >(
+	key: string,
+	defaultValue: T
+): T => {
+	try {
+		const saved = window?.localStorage?.getItem( key );
+		if ( saved ) {
+			const parsed = JSON.parse( saved ) as T;
+			// If the parsed value is an object (and not null or array), merge with defaultValue
+			if (
+				typeof parsed === 'object' &&
+				parsed !== null &&
+				! Array.isArray( parsed )
+			) {
+				return { ...defaultValue, ...( parsed as Partial< T > ) };
+			}
+			// For primitive values (string, number, boolean, null), return directly
+			return parsed;
+		}
+	} catch ( error ) {
+		// eslint-disable-next-line no-console
+		console.warn(
+			`Failed to load data from localStorage (key: ${ key }):`,
+			error
+		);
+	}
+	return defaultValue;
+};
+
+/**
+ * Save data to localStorage with error handling
+ * @param key  - The localStorage key to write to
+ * @param data - The data to save
+ */
+export const saveToLocalStorage = < T >( key: string, data: T ): void => {
+	try {
+		localStorage.setItem( key, JSON.stringify( data ) );
+	} catch ( error ) {
+		// eslint-disable-next-line no-console
+		console.warn(
+			`Failed to save data to localStorage (key: ${ key }):`,
+			error
+		);
+	}
+};
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index e2e1a743621459..818404c98979dc 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -78,11 +78,11 @@ export function createSyncManager(): SyncManager {
 	/**
 	 * Load an entity for syncing and manage its lifecycle.
 	 *
-	 * @param {SyncConfig}        syncConfig  Sync configuration for the object type.
-	 * @param {ObjectType}        objectType  Object type.
-	 * @param {ObjectID}          objectId    Object ID.
-	 * @param {ObjectData}        record      Entity record representing this object type.
-	 * @param {RecordHandlers}    handlers    Handlers for updating and fetching the record.
+	 * @param {SyncConfig}     syncConfig Sync configuration for the object type.
+	 * @param {ObjectType}     objectType Object type.
+	 * @param {ObjectID}       objectId   Object ID.
+	 * @param {ObjectData}     record     Entity record representing this object type.
+	 * @param {RecordHandlers} handlers   Handlers for updating and fetching the record.
 	 */
 	async function loadEntity(
 		syncConfig: SyncConfig,
diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index 9f48bf3aab62ee..565542a32e8588 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -59,6 +59,7 @@ describe( 'SyncManager', () => {
 		mockCurrentUser = {
 			id: 1,
 			name: 'Test User',
+			slug: 'test-user',
 			avatar_urls: {
 				'24': 'https://example.com/avatar.jpg',
 				'48': 'https://example.com/avatar-48.jpg',
diff --git a/packages/sync/src/user-utils.ts b/packages/sync/src/user-utils.ts
new file mode 100644
index 00000000000000..1a7a9a1ab25589
--- /dev/null
+++ b/packages/sync/src/user-utils.ts
@@ -0,0 +1,139 @@
+import type { UserInfo } from './awareness/awareness-types';
+import { loadFromLocalStorage, saveToLocalStorage } from './local-storage';
+
+/**
+ * The color palette for the user highlight.
+ */
+const COLOR_PALETTE = [
+	'#3858E9', // blueberry
+	'#B42AED', // purple
+	'#E33184', // pink
+	'#F3661D', // orange
+	'#ECBD3A', // yellow
+	'#97FE17', // green
+	'#00FDD9', // teal
+	'#37C5F0', // cyan
+];
+
+const LOCAL_STORAGE_KEY = 'gutenberg-rtc-preferred-color';
+
+/**
+ * Generate a random integer between min and max, inclusive.
+ *
+ * @param min - The minimum value.
+ * @param max - The maximum value.
+ * @return A random integer between min and max.
+ */
+function generateRandomInt( min: number, max: number ): number {
+	return Math.floor( Math.random() * ( max - min + 1 ) ) + min;
+}
+
+/**
+ * Get a unique user color from the palette, or generate a variation if none are available.
+ * If the previously used color is available from localStorage, use it.
+ *
+ * @param existingColors - Colors that are already in use.
+ * @return The new user color, in hex format.
+ */
+export function getNewUserColor( existingColors: string[] ): string {
+	const availableColors = COLOR_PALETTE.filter(
+		( color ) => ! existingColors.includes( color )
+	);
+
+	const preferredColor = loadFromLocalStorage< string | null >(
+		LOCAL_STORAGE_KEY,
+		null
+	);
+
+	let hexColor: string;
+
+	if ( preferredColor && availableColors.includes( preferredColor ) ) {
+		hexColor = preferredColor;
+	} else if ( availableColors.length > 0 ) {
+		const randomIndex = generateRandomInt( 0, availableColors.length - 1 );
+		hexColor = availableColors[ randomIndex ];
+	} else {
+		// All colors are used, generate a variation of a random palette color
+		const randomIndex = generateRandomInt( 0, COLOR_PALETTE.length - 1 );
+		const baseColor = COLOR_PALETTE[ randomIndex ];
+		hexColor = generateColorVariation( baseColor );
+	}
+
+	saveToLocalStorage( LOCAL_STORAGE_KEY, hexColor );
+	return hexColor;
+}
+
+/**
+ * Generate a variation of a hex color by adjusting its lightness.
+ *
+ * @param hexColor - The base hex color (e.g., '#3858E9').
+ * @return A varied hex color.
+ */
+function generateColorVariation( hexColor: string ): string {
+	// Parse hex to RGB
+	const r = parseInt( hexColor.slice( 1, 3 ), 16 );
+	const g = parseInt( hexColor.slice( 3, 5 ), 16 );
+	const b = parseInt( hexColor.slice( 5, 7 ), 16 );
+
+	// Apply a random lightness shift (-30 to +30)
+	const shift = generateRandomInt( -30, 30 );
+	const newR = Math.min( 255, Math.max( 0, r + shift ) );
+	const newG = Math.min( 255, Math.max( 0, g + shift ) );
+	const newB = Math.min( 255, Math.max( 0, b + shift ) );
+
+	// Convert back to hex
+	const toHex = ( n: number ) => n.toString( 16 ).padStart( 2, '0' ).toUpperCase();
+	return `#${ toHex( newR ) }${ toHex( newG ) }${ toHex( newB ) }`;
+}
+
+/**
+ * Get the browser name from the user agent.
+ * @return The browser name.
+ */
+export function getBrowserName(): string {
+	const userAgent = window.navigator.userAgent;
+	let browserName = 'Unknown';
+
+	if ( userAgent.includes( 'Firefox' ) ) {
+		browserName = 'Firefox';
+	} else if ( userAgent.includes( 'Edg' ) ) {
+		browserName = 'Microsoft Edge';
+	} else if (
+		userAgent.includes( 'Chrome' ) &&
+		! userAgent.includes( 'Edg' )
+	) {
+		browserName = 'Chrome';
+	} else if (
+		userAgent.includes( 'Safari' ) &&
+		! userAgent.includes( 'Chrome' )
+	) {
+		browserName = 'Safari';
+	} else if (
+		userAgent.includes( 'MSIE' ) ||
+		userAgent.includes( 'Trident' )
+	) {
+		browserName = 'Internet Explorer';
+	} else if ( userAgent.includes( 'Opera' ) || userAgent.includes( 'OPR' ) ) {
+		browserName = 'Opera';
+	}
+
+	return browserName;
+}
+
+export function areUserInfosEqual(
+	userInfo1?: UserInfo,
+	userInfo2?: UserInfo
+): boolean {
+	if ( ! userInfo1 || ! userInfo2 ) {
+		return userInfo1 === userInfo2;
+	}
+
+	if ( Object.keys( userInfo1 ).length !== Object.keys( userInfo2 ).length ) {
+		return false;
+	}
+
+	return Object.entries( userInfo1 ).every( ( [ key, value ] ) => {
+		// Update this function with any non-primitive fields added to UserInfo.
+		return value === userInfo2[ key as keyof UserInfo ];
+	} );
+}
diff --git a/packages/sync/src/utils.ts b/packages/sync/src/utils.ts
index 3ae24d1e5a344a..baa9373223f27d 100644
--- a/packages/sync/src/utils.ts
+++ b/packages/sync/src/utils.ts
@@ -106,61 +106,3 @@ export function areMapsEqual< Key, Value >(
 
 	return true;
 }
-
-/**
- * Compare two user infos for equality.
- * @param userInfo1 - The first user info to compare.
- * @param userInfo2 - The second user info to compare.
- * @return True if the user infos are equal, false otherwise.
- */
-export function areUserInfosEqual(
-	userInfo1?: UserInfo,
-	userInfo2?: UserInfo
-): boolean {
-	if ( ! userInfo1 || ! userInfo2 ) {
-		return userInfo1 === userInfo2;
-	}
-
-	if ( Object.keys( userInfo1 ).length !== Object.keys( userInfo2 ).length ) {
-		return false;
-	}
-
-	return Object.entries( userInfo1 ).every( ( [ key, value ] ) => {
-		// Update this function with any non-primitive fields added to UserInfo.
-		return value === userInfo2[ key as keyof UserInfo ];
-	} );
-}
-
-/**
- * Get the browser name from the user agent.
- * @return The browser name.
- */
-export function getBrowserName(): string {
-	const userAgent = window.navigator.userAgent;
-	let browserName = 'Unknown';
-
-	if ( userAgent.includes( 'Firefox' ) ) {
-		browserName = 'Firefox';
-	} else if ( userAgent.includes( 'Edg' ) ) {
-		browserName = 'Microsoft Edge';
-	} else if (
-		userAgent.includes( 'Chrome' ) &&
-		! userAgent.includes( 'Edg' )
-	) {
-		browserName = 'Chrome';
-	} else if (
-		userAgent.includes( 'Safari' ) &&
-		! userAgent.includes( 'Chrome' )
-	) {
-		browserName = 'Safari';
-	} else if (
-		userAgent.includes( 'MSIE' ) ||
-		userAgent.includes( 'Trident' )
-	) {
-		browserName = 'Internet Explorer';
-	} else if ( userAgent.includes( 'Opera' ) || userAgent.includes( 'OPR' ) ) {
-		browserName = 'Opera';
-	}
-
-	return browserName;
-}

From cf05627081ab88b92d6b49be46707662eae75168 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Fri, 16 Jan 2026 15:46:45 +1100
Subject: [PATCH 04/30] Attempting to fix the sync

---
 .../sync/src/awareness/awareness-manager.ts   | 19 +++++++--
 .../awareness/post-editor-awareness-state.ts  | 41 +++++++++++++++++--
 2 files changed, 53 insertions(+), 7 deletions(-)

diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 37fd2de05abfe3..68eb20c00f81a9 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -33,14 +33,23 @@ function getUserInfo(
 	wpUser: WordPressUserInfo
 ): UserInfo {
 	const states = awareness.getStates();
+	console.log( 'clientID:', awareness.clientID );
+	console.log( 'states snapshot:', JSON.stringify( Object.fromEntries( states ) ) );
 	const otherUserColors = Array.from( states.entries() )
 		.filter(
-			( [ clientId, state ] ) =>
-				state.userInfo && clientId !== awareness.clientID
+			( [ clientId, state ] ) => {
+				console.log( { clientId, state } );
+				return state.userInfo && clientId !== awareness.clientID;
+			}
 		)
-		.map( ( [ _clientId, state ] ) => state.userInfo.color )
+		.map( ( [ _clientId, state ] ) => {
+			console.log( { state } );
+			return state.userInfo?.color;
+		} )
 		.filter( Boolean );
 
+	console.log( { otherUserColors } );
+
 	return {
 		...wpUser,
 		browserType: getBrowserName(),
@@ -86,6 +95,10 @@ export async function createAwareness(
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
+
+		// Wait for initial sync before assigning color
+		await new Promise( ( resolve ) => setTimeout( resolve, 500 ) );
+
 		const userInfo = getUserInfo( awareness, currentUser );
 		awareness.setUp( userInfo );
 		awarenessInstances.set(
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 9ebae5b554e6fd..a2ca03de078bb6 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -8,7 +8,7 @@ import * as Y from 'yjs';
 import type { PostEditorState, UserInfo } from './awareness-types';
 import { AwarenessState } from './awareness-state';
 import { areUserInfosEqual } from '../user-utils';
-import { CRDT_RECORD_MAP_KEY } from '../config';
+import { CRDT_RECORD_METADATA_SAVED_AT_KEY, CRDT_RECORD_METADATA_SAVED_BY_KEY, CRDT_RECORD_METADATA_MAP_KEY } from '../config';
 
 export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
 	protected equalityFieldChecks = {
@@ -22,10 +22,43 @@ export class PostEditorAwarenessState extends AwarenessState< PostEditorState >
 	}
 
 	private subscribeToCRDTChanges(): void {
-		const recordMap = this.doc.getMap( CRDT_RECORD_MAP_KEY );
+		const now = Date.now();
+		const recordMeta = this.doc.getMap( CRDT_RECORD_METADATA_MAP_KEY );
 
-		recordMap.observeDeep( ( changes ) => {
-			console.log( changes );
+		recordMeta.observe( ( event: Y.YMapEvent< unknown >, transaction: Y.Transaction ) => {
+			if ( transaction.local ) {
+				return;
+			}
+
+			event.keysChanged.forEach( ( key: string ) => {
+				switch ( key ) {
+					// A remote user has saved the document.
+					case CRDT_RECORD_METADATA_SAVED_AT_KEY: {
+						const savedTimestamp = recordMeta.get( CRDT_RECORD_METADATA_SAVED_AT_KEY );
+						const remoteClientId = recordMeta.get( CRDT_RECORD_METADATA_SAVED_BY_KEY );
+
+						// Type / "undefined" guard.
+						if ( 'number' !== typeof remoteClientId || 'number' !== typeof savedTimestamp ) {
+							break;
+						}
+
+						const userState = this.getStates().get( remoteClientId );
+
+						if (
+							// Ignore if the savedAt timestamp is older than our session
+							now > savedTimestamp ||
+							// Ignore if we don't have a user state for the client ID
+							! userState ||
+							// Ignore if this is our own saved event (can happen on refresh or reconnect)
+							userState.userInfo.id === this.getLocalStateField( 'userInfo' )?.id
+						) {
+							break;
+						}
+
+						console.log( 'Document was saved by client ID', remoteClientId );
+					}
+				}
+			} );
 		} );
 	}
 

From 2c1d5cf274cc2c0995652928be07b56e3a031245 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 08:23:44 +1100
Subject: [PATCH 05/30] Add a comment explining the bug

---
 .../sync/src/awareness/awareness-manager.ts   | 20 ++++---------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 68eb20c00f81a9..64d0499fe63283 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -33,23 +33,15 @@ function getUserInfo(
 	wpUser: WordPressUserInfo
 ): UserInfo {
 	const states = awareness.getStates();
-	console.log( 'clientID:', awareness.clientID );
-	console.log( 'states snapshot:', JSON.stringify( Object.fromEntries( states ) ) );
+	// TODO: There is a timing issue here. The other users aren't yet synced, and as a result the same color could be assigned to multiple users.
 	const otherUserColors = Array.from( states.entries() )
 		.filter(
-			( [ clientId, state ] ) => {
-				console.log( { clientId, state } );
-				return state.userInfo && clientId !== awareness.clientID;
-			}
+			( [ clientId, state ] ) =>
+				state.userInfo && clientId !== awareness.clientID
 		)
-		.map( ( [ _clientId, state ] ) => {
-			console.log( { state } );
-			return state.userInfo?.color;
-		} )
+		.map( ( [ _clientId, state ] ) => state.userInfo.color )
 		.filter( Boolean );
 
-	console.log( { otherUserColors } );
-
 	return {
 		...wpUser,
 		browserType: getBrowserName(),
@@ -95,10 +87,6 @@ export async function createAwareness(
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
-
-		// Wait for initial sync before assigning color
-		await new Promise( ( resolve ) => setTimeout( resolve, 500 ) );
-
 		const userInfo = getUserInfo( awareness, currentUser );
 		awareness.setUp( userInfo );
 		awarenessInstances.set(

From 8772cb2e4043f89d8fc67b10eb47ce0bae055cb9 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 15:09:32 +1100
Subject: [PATCH 06/30] Add support for selection

---
 package-lock.json                             |   1 +
 packages/core-data/src/resolvers.js           |   3 +-
 packages/sync/README.md                       |  10 +
 packages/sync/package.json                    |   4 +-
 .../sync/src/awareness/awareness-manager.ts   |   2 +-
 .../sync/src/awareness/awareness-state.ts     |  37 +-
 .../sync/src/awareness/awareness-types.ts     |  36 +-
 .../awareness/post-editor-awareness-state.ts  | 138 +++++--
 packages/sync/src/config.ts                   |  10 +
 packages/sync/src/manager.ts                  |   1 +
 packages/sync/src/selection-utils.ts          | 366 ++++++++++++++++++
 packages/sync/src/types.ts                    |   5 +-
 packages/sync/src/user-utils.ts               |   3 +-
 packages/sync/src/utils.ts                    |   1 -
 packages/sync/tsconfig.json                   |   2 +
 15 files changed, 566 insertions(+), 53 deletions(-)
 create mode 100644 packages/sync/src/selection-utils.ts

diff --git a/package-lock.json b/package-lock.json
index 75c8294415d78c..3e70bd8e60d1e0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -54919,6 +54919,7 @@
 			"license": "GPL-2.0-or-later",
 			"dependencies": {
 				"@types/diff": "7.0.2",
+				"@wordpress/block-editor": "file:../block-editor",
 				"@wordpress/hooks": "file:../hooks",
 				"@wordpress/undo-manager": "file:../undo-manager",
 				"@wordpress/url": "file:../url",
diff --git a/packages/core-data/src/resolvers.js b/packages/core-data/src/resolvers.js
index 05a266f11d7b78..c990c2ad226f72 100644
--- a/packages/core-data/src/resolvers.js
+++ b/packages/core-data/src/resolvers.js
@@ -192,7 +192,7 @@ export const getEntityRecord =
 						recordWithTransients,
 						{
 							// Handle edits sourced from the sync manager.
-							editRecord: ( edits ) => {
+							editRecord: ( edits, options = {} ) => {
 								if ( ! Object.keys( edits ).length ) {
 									return;
 								}
@@ -206,6 +206,7 @@ export const getEntityRecord =
 									meta: {
 										undo: undefined,
 									},
+									options,
 								} );
 							},
 							// Get the current entity record (with edits)
diff --git a/packages/sync/README.md b/packages/sync/README.md
index 2dd2b37cc4056c..8828c965b2db6e 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -50,6 +50,16 @@ Origin string for CRDT document changes originating from the local editor.
 
 Origin string for CRDT document changes originating from the sync manager.
 
+### setConnectionStatus
+
+Set the current user's connection status in the awareness instance for the given object type and object ID.
+
+_Parameters_
+
+-   _objectType_ `ObjectType`: Object type.
+-   _objectId_ `ObjectID | null`: Object ID.
+-   _isConnected_ `boolean`: Connection status.
+
 ### WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE
 
 WordPress meta key used to persist the CRDT document for an entity.
diff --git a/packages/sync/package.json b/packages/sync/package.json
index 92c13425be0673..959c51dc1201c7 100644
--- a/packages/sync/package.json
+++ b/packages/sync/package.json
@@ -30,7 +30,6 @@
 		"*.md"
 	],
 	"main": "build/index.cjs",
-	"wpScript": true,
 	"module": "build-module/index.mjs",
 	"exports": {
 		".": {
@@ -41,10 +40,13 @@
 		"./package.json": "./package.json"
 	},
 	"react-native": "src/index",
+	"wpScript": true,
 	"types": "build-types",
 	"sideEffects": false,
 	"dependencies": {
 		"@types/diff": "7.0.2",
+		"@wordpress/block-editor": "file:../block-editor",
+		"@wordpress/data": "file:../data",
 		"@wordpress/hooks": "file:../hooks",
 		"@wordpress/undo-manager": "file:../undo-manager",
 		"@wordpress/url": "file:../url",
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 64d0499fe63283..e9b979e384a2d1 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -39,7 +39,7 @@ function getUserInfo(
 			( [ clientId, state ] ) =>
 				state.userInfo && clientId !== awareness.clientID
 		)
-		.map( ( [ _clientId, state ] ) => state.userInfo.color )
+		.map( ( [ , state ] ) => state.userInfo.color )
 		.filter( Boolean );
 
 	return {
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 95ab2c8a6bb1f6..848208db6be4a9 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -10,6 +10,7 @@ import {
 } from './awareness-types';
 import { getTypedKeys, areMapsEqual } from '../utils';
 import { REMOVAL_DELAY_IN_MS } from '../config';
+import type { RecordHandlers } from '../types';
 
 type AwarenessClientID = number;
 
@@ -145,14 +146,16 @@ export abstract class AwarenessState<
 	 * value -- even if it hasn't yet been set on the awareness instance.
 	 */
 	private myThrottledState: Partial< State > = {};
+	private throttleTimeouts: Map< string, NodeJS.Timeout > = new Map();
 
 	/** CUSTOM METHODS */
 
 	/**
-	 * Set up.
-	 * @param userInfo
+	 * Set up the awareness state.
+	 * @param _recordHandlers - Record handlers.
+	 * @param userInfo        - User info.
 	 */
-	public setUp( userInfo: UserInfo ): void {
+	public setUp( _recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
 		this.setLocalStateField( 'userInfo', userInfo );
 
 		this.on(
@@ -201,6 +204,34 @@ export abstract class AwarenessState<
 		};
 	}
 
+	/**
+	 * Set a local state field on an awareness document with throttle. See caveats
+	 * of this.setLocalStateField.
+	 * @param field
+	 * @param value
+	 * @param wait
+	 */
+	public setThrottledLocalStateField<
+		FieldName extends string & keyof State,
+	>( field: FieldName, value: State[ FieldName ], wait: number ): void {
+		this.setLocalStateField( field, value );
+
+		this.throttleTimeouts.set(
+			field,
+			setTimeout( () => {
+				this.throttleTimeouts.delete( field );
+				if ( this.myThrottledState[ field ] ) {
+					this.setLocalStateField(
+						field,
+						this.myThrottledState[ field ]
+					);
+
+					delete this.myThrottledState[ field ];
+				}
+			}, wait )
+		);
+	}
+
 	/**
 	 * Set the current user's connection status as awareness state.
 	 * @param isConnected
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index bc4e5eb93364ff..ce041c73549327 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -1,6 +1,7 @@
 import { Awareness } from 'y-protocols/awareness';
 
 import { getRecordValue } from '../utils';
+import type { SelectionState } from '../selection-utils';
 
 /**
  * Extended Awareness class with typed state accessors.
@@ -81,15 +82,44 @@ export type EnhancedState< State extends BaseState > = State & {
 	isMe: boolean;
 };
 
+/**
+ * A block selection object.
+ *
+ * In order to avoid circular dependencies, we define it here instead of importing
+ * the WPBlockSelection interface from @wordpress/editor.
+ */
+export type WPBlockSelection = {
+	/**
+	 * A block client ID.
+	 */
+	clientId: string;
+	/**
+	 * A block attribute key.
+	 */
+	attributeKey: string;
+	/**
+	 * An attribute value offset, based on the rich
+	 * text value. See `wp.richText.create`.
+	 */
+	offset: number;
+};
+
 export type EqualityFieldCheck<
 	State extends BaseState,
 	FieldName extends keyof State,
 > = ( value1?: State[ FieldName ], value2?: State[ FieldName ] ) => boolean;
 
+/**
+ * The editor state includes information about the user's current selection.
+ */
+export interface EditorState {
+	selection: SelectionState;
+}
+
 /**
  * The post editor state extends the base state with information used to render
  * presence indicators in the post editor.
- *
- * TODO: Add in the presence indicators.
  */
-export interface PostEditorState extends BaseState {}
+export interface PostEditorState extends BaseState {
+	editorState?: EditorState;
+}
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index a2ca03de078bb6..8f27466ef780c6 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -1,66 +1,122 @@
 /**
  * External dependencies
  */
-import * as Y from 'yjs';
+import type * as Y from 'yjs';
+
+/**
+ * WordPress dependencies
+ */
+import { store as blockEditorStore } from '@wordpress/block-editor';
+import { select, subscribe } from '@wordpress/data';
+// @ts-expect-error No exported types for block editor store selectors.
+import { type BlockEditorStoreSelectors } from '@wordpress/block-editor/build-types/store/selectors';
+
 /**
  * Internal dependencies
  */
-import type { PostEditorState, UserInfo } from './awareness-types';
+import type {
+	PostEditorState,
+	UserInfo,
+	WPBlockSelection,
+} from './awareness-types';
+import type { RecordHandlers } from '../types';
 import { AwarenessState } from './awareness-state';
 import { areUserInfosEqual } from '../user-utils';
-import { CRDT_RECORD_METADATA_SAVED_AT_KEY, CRDT_RECORD_METADATA_SAVED_BY_KEY, CRDT_RECORD_METADATA_MAP_KEY } from '../config';
+import {
+	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
+	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
+	CRDT_RECORD_MAP_KEY,
+} from '../config';
+import type { SelectableBlock } from '../selection-utils';
+import {
+	updateSelectionInEntityRecord,
+	getSelectionState,
+	areEditorStatesEqual,
+} from '../selection-utils';
 
 export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
 	protected equalityFieldChecks = {
+		editorState: areEditorStatesEqual,
 		userInfo: areUserInfosEqual,
 	};
 
-	public setUp( userInfo: UserInfo ): void {
-		super.setUp( userInfo );
+	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
+		super.setUp( recordHandlers, userInfo );
 
-		this.subscribeToCRDTChanges();
+		this.subscribeToSelectionChanges( recordHandlers );
 	}
 
-	private subscribeToCRDTChanges(): void {
-		const now = Date.now();
-		const recordMeta = this.doc.getMap( CRDT_RECORD_METADATA_MAP_KEY );
+	private subscribeToSelectionChanges( handlers: RecordHandlers ): void {
+		const {
+			getSelectionStart,
+			getSelectionEnd,
+			getSelectedBlocksInitialCaretPosition,
+		} = select( blockEditorStore ) as BlockEditorStoreSelectors;
+
+		// Keep track of the current selection in the outer scope so we can compare
+		// in the subscription.
+		let selectionStart = getSelectionStart();
+		let selectionEnd = getSelectionEnd();
+		let localCursorTimeout: NodeJS.Timeout | null = null;
+
+		// Provided type is generic `Function`.
+
+		subscribe( () => {
+			const newSelectionStart = getSelectionStart();
+			const newSelectionEnd = getSelectionEnd();
 
-		recordMeta.observe( ( event: Y.YMapEvent< unknown >, transaction: Y.Transaction ) => {
-			if ( transaction.local ) {
+			if (
+				newSelectionStart === selectionStart &&
+				newSelectionEnd === selectionEnd
+			) {
 				return;
 			}
 
-			event.keysChanged.forEach( ( key: string ) => {
-				switch ( key ) {
-					// A remote user has saved the document.
-					case CRDT_RECORD_METADATA_SAVED_AT_KEY: {
-						const savedTimestamp = recordMeta.get( CRDT_RECORD_METADATA_SAVED_AT_KEY );
-						const remoteClientId = recordMeta.get( CRDT_RECORD_METADATA_SAVED_BY_KEY );
-
-						// Type / "undefined" guard.
-						if ( 'number' !== typeof remoteClientId || 'number' !== typeof savedTimestamp ) {
-							break;
-						}
-
-						const userState = this.getStates().get( remoteClientId );
-
-						if (
-							// Ignore if the savedAt timestamp is older than our session
-							now > savedTimestamp ||
-							// Ignore if we don't have a user state for the client ID
-							! userState ||
-							// Ignore if this is our own saved event (can happen on refresh or reconnect)
-							userState.userInfo.id === this.getLocalStateField( 'userInfo' )?.id
-						) {
-							break;
-						}
-
-						console.log( 'Document was saved by client ID', remoteClientId );
-					}
-				}
-			} );
+			selectionStart = newSelectionStart;
+			selectionEnd = newSelectionEnd;
+
+			// Typically selection position is only persisted after typing in a block, which
+			// can cause selection position to be reset by other users making block updates.
+			// Ensure we update the controlled selection right away, persisting our cursor position locally.
+			void updateSelectionInEntityRecord(
+				handlers,
+				selectionStart,
+				selectionEnd,
+				getSelectedBlocksInitialCaretPosition()
+			);
+
+			// We receive two selection changes in quick succession
+			// from local selection events:
+			//   { clientId: "123...", attributeKey: "content", offset: undefined }
+			//   { clientId: "123...", attributeKey: "content", offset: 554 }
+			// Add a short debounce to avoid sending the first selection change.
+			if ( localCursorTimeout ) {
+				clearTimeout( localCursorTimeout );
+			}
+
+			localCursorTimeout = setTimeout( () => {
+				this.updateSelectionState( selectionStart, selectionEnd );
+			}, LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS );
 		} );
 	}
 
-	// TODO: Add in subscription for user selection changes.
+	private updateSelectionState(
+		selectionStart: WPBlockSelection,
+		selectionEnd: WPBlockSelection
+	): void {
+		const ydoc = this.doc.getMap( CRDT_RECORD_MAP_KEY );
+		const yBlocks = ydoc.get( 'blocks' ) as Y.Array< SelectableBlock >;
+		const selection = getSelectionState(
+			selectionStart,
+			selectionEnd,
+			yBlocks
+		);
+
+		// Throttle remote awareness updates.
+		this.setThrottledLocalStateField(
+			'editorState',
+			{ selection },
+			AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
+		);
+	}
 }
diff --git a/packages/sync/src/config.ts b/packages/sync/src/config.ts
index 11eec60c670699..67bb5cf108e07a 100644
--- a/packages/sync/src/config.ts
+++ b/packages/sync/src/config.ts
@@ -63,3 +63,13 @@ export const WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE = '_crdt_document';
  * Delay in milliseconds before removing a user from presence indicators.
  */
 export const REMOVAL_DELAY_IN_MS = 5000;
+
+/**
+ * Delay in milliseconds before updating the cursor position.
+ */
+export const LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS = 500;
+
+/**
+ * Delay in milliseconds before throttling the cursor position updates.
+ */
+export const AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS = 100;
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index 05ed5f0234db72..4f856aad1ca66a 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -182,6 +182,7 @@ export function createSyncManager(): SyncManager {
 			objectType,
 			objectId,
 			ydoc,
+			handlers,
 			currentUser
 		);
 
diff --git a/packages/sync/src/selection-utils.ts b/packages/sync/src/selection-utils.ts
new file mode 100644
index 00000000000000..51a70a73fa5d62
--- /dev/null
+++ b/packages/sync/src/selection-utils.ts
@@ -0,0 +1,366 @@
+/**
+ * External dependencies
+ */
+import * as Y from 'yjs';
+
+/**
+ * Internal dependencies
+ */
+import type { EditorState } from './awareness/awareness-types';
+import { type WPBlockSelection } from './awareness/awareness-types';
+import type { RecordHandlers } from './types';
+
+/**
+ * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
+ */
+type BlockClientId = string;
+type BlockInnerBlocks = Y.Array< SelectableBlock >;
+type BlockAttributes = Y.Map< Y.Text >;
+
+/**
+ * A block that can be selected.
+ */
+export type SelectableBlock = Y.Map<
+	BlockClientId | BlockAttributes | BlockInnerBlocks
+>;
+
+/**
+ * The type of selection.
+ */
+export enum SelectionType {
+	None = 'none',
+	Cursor = 'cursor',
+	SelectionInOneBlock = 'selection-in-one-block',
+	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
+	WholeBlock = 'whole-block',
+}
+
+/**
+ * The position of the cursor.
+ */
+export type CursorPosition = {
+	relativePosition: Y.RelativePosition;
+
+	// Also store the absolute offset index of the cursor from the perspective
+	// of the user who is updating the selection.
+	//
+	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
+	// on relativePosition for the most up-to-date positioning.
+	//
+	// This is used because local Y.Text changes (e.g. adding or deleting a character)
+	// can result in the same relative position if it is pinned to an unchanged
+	// character. With both of these values as editor state, a change in perceived
+	// position will always result in a redraw.
+	absoluteOffset: number;
+};
+
+export type SelectionNone = {
+	// The user has not made a selection.
+	type: SelectionType.None;
+};
+
+export type SelectionCursor = {
+	// The user has a cursor position in a block with no text highlighted.
+	type: SelectionType.Cursor;
+	blockId: string;
+	cursorPosition: CursorPosition;
+};
+
+export type SelectionInOneBlock = {
+	// The user has highlighted text in a single block.
+	type: SelectionType.SelectionInOneBlock;
+	blockId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionInMultipleBlocks = {
+	// The user has highlighted text over multiple blocks.
+	type: SelectionType.SelectionInMultipleBlocks;
+	blockStartId: string;
+	blockEndId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionWholeBlock = {
+	// The user has a non-text block selected, like an image block.
+	type: SelectionType.WholeBlock;
+	blockId: string;
+};
+
+export type SelectionState =
+	| SelectionNone
+	| SelectionCursor
+	| SelectionInOneBlock
+	| SelectionInMultipleBlocks
+	| SelectionWholeBlock;
+
+/**
+ * Converts WordPress block editor selection to a SelectionState.
+ *
+ * @param selectionStart - The start position of the selection
+ * @param selectionEnd   - The end position of the selection
+ * @param yBlocks
+ * @return The SelectionState
+ */
+export function getSelectionState(
+	selectionStart: WPBlockSelection,
+	selectionEnd: WPBlockSelection,
+	yBlocks: Y.Array< SelectableBlock >
+): SelectionState {
+	const isSelectionEmpty = Object.keys( selectionStart ).length === 0;
+	const noSelection: SelectionNone = {
+		type: SelectionType.None,
+	};
+
+	if ( isSelectionEmpty ) {
+		// Case 1: No selection
+		return noSelection;
+	}
+
+	// When the page initially loads, selectionStart can contain an empty object `{}`.
+	const isSelectionInOneBlock =
+		selectionStart.clientId === selectionEnd.clientId;
+	const isCursorOnly =
+		isSelectionInOneBlock && selectionStart.offset === selectionEnd.offset;
+	const isSelectionAWholeBlock =
+		isSelectionInOneBlock &&
+		selectionStart.offset === undefined &&
+		selectionEnd.offset === undefined;
+
+	if ( isSelectionAWholeBlock ) {
+		// Case 2: A whole block is selected.
+		return {
+			type: SelectionType.WholeBlock,
+			blockId: selectionStart.clientId,
+		};
+	} else if ( isCursorOnly ) {
+		// Case 3: Cursor only, no text selected
+		const cursorPosition = getCursorPosition( selectionStart, yBlocks );
+
+		if ( ! cursorPosition ) {
+			// If we can't find the cursor position in block text, treat it as a non-selection.
+			return noSelection;
+		}
+
+		return {
+			type: SelectionType.Cursor,
+			blockId: selectionStart.clientId,
+			cursorPosition,
+		};
+	} else if ( isSelectionInOneBlock ) {
+		// Case 4: Selection in a single block
+		const cursorStartPosition = getCursorPosition(
+			selectionStart,
+			yBlocks
+		);
+		const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
+
+		if ( ! cursorStartPosition || ! cursorEndPosition ) {
+			// If we can't find the cursor positions in block text, treat it as a non-selection.
+			return noSelection;
+		}
+
+		return {
+			type: SelectionType.SelectionInOneBlock,
+			blockId: selectionStart.clientId,
+			cursorStartPosition,
+			cursorEndPosition,
+		};
+	}
+
+	// Caes 5: Selection in multiple blocks
+	const cursorStartPosition = getCursorPosition( selectionStart, yBlocks );
+	const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
+	if ( ! cursorStartPosition || ! cursorEndPosition ) {
+		// If we can't find the cursor positions in block text, treat it as a non-selection.
+		return noSelection;
+	}
+
+	return {
+		type: SelectionType.SelectionInMultipleBlocks,
+		blockStartId: selectionStart.clientId,
+		blockEndId: selectionEnd.clientId,
+		cursorStartPosition,
+		cursorEndPosition,
+	};
+}
+
+/**
+ * Update the entity record with the current user's selection.
+ *
+ * @param handlers        - Record handlers.
+ * @param selectionStart  - The start position of the selection.
+ * @param selectionEnd    - The end position of the selection.
+ * @param initialPosition - The initial position of the selection.
+ */
+export async function updateSelectionInEntityRecord(
+	handlers: RecordHandlers,
+	selectionStart: WPBlockSelection,
+	selectionEnd: WPBlockSelection,
+	initialPosition: number | null
+): Promise< void > {
+	if ( ! selectionStart.clientId ) {
+		return;
+	}
+
+	// Send an entityRecord `selection` update if we have a selection.
+	//
+	// Normally WordPress updates the `selection` property of the post when changes are made to blocks.
+	// In a multi-user setup, block changes can occur from other users. When an entity is updated from another
+	// user's changes, useBlockSync() in Gutenberg will reset the user's selection to the last saved selection.
+	//
+	// Manually adding an edit for each movement ensures that other user's changes to the document will
+	// not cause the local user's selection to reset to the last local change location.
+	const edits = {
+		selection: { selectionStart, selectionEnd, initialPosition },
+	};
+
+	const options = {
+		undoIgnore: true,
+	};
+
+	handlers.editRecord( edits, options );
+}
+
+export function getCursorPosition(
+	selection: WPBlockSelection,
+	blocks: Y.Array< SelectableBlock >
+): CursorPosition | null {
+	const block = findBlockByClientId( selection.clientId, blocks );
+	if ( ! block ) {
+		return null;
+	}
+
+	const attributes = block.get( 'attributes' ) as Y.Map< Y.Text >;
+	const currentYText = attributes.get( selection.attributeKey ) as Y.Text;
+
+	const relativePosition = Y.createRelativePositionFromTypeIndex(
+		currentYText,
+		selection.offset
+	);
+
+	return {
+		relativePosition,
+		absoluteOffset: selection.offset,
+	};
+}
+
+function findBlockByClientId(
+	blockId: string,
+	blocks: Y.Array< SelectableBlock >
+): SelectableBlock | null {
+	for ( const block of blocks ) {
+		if ( block.get( 'clientId' ) === blockId ) {
+			return block;
+		}
+
+		const innerBlocks = block.get( 'innerBlocks' ) as BlockInnerBlocks;
+
+		if ( innerBlocks.length > 0 ) {
+			const innerBlock = findBlockByClientId(
+				blockId,
+				block.get( 'innerBlocks' ) as Y.Array< SelectableBlock >
+			);
+
+			if ( innerBlock ) {
+				return innerBlock;
+			}
+		}
+	}
+
+	return null;
+}
+
+export function areSelectionsEqual(
+	selection1: SelectionState,
+	selection2: SelectionState
+): boolean {
+	if ( selection1.type !== selection2.type ) {
+		return false;
+	}
+
+	switch ( selection1.type ) {
+		case SelectionType.None:
+			return true;
+
+		case SelectionType.Cursor:
+			return (
+				selection1.blockId ===
+					( selection2 as SelectionCursor ).blockId &&
+				areCursorPositionsEqual(
+					selection1.cursorPosition,
+					( selection2 as SelectionCursor ).cursorPosition
+				)
+			);
+
+		case SelectionType.SelectionInOneBlock:
+			return (
+				selection1.blockId ===
+					( selection2 as SelectionInOneBlock ).blockId &&
+				areCursorPositionsEqual(
+					selection1.cursorStartPosition,
+					( selection2 as SelectionInOneBlock ).cursorStartPosition
+				) &&
+				areCursorPositionsEqual(
+					selection1.cursorEndPosition,
+					( selection2 as SelectionInOneBlock ).cursorEndPosition
+				)
+			);
+
+		case SelectionType.SelectionInMultipleBlocks:
+			return (
+				selection1.blockStartId ===
+					( selection2 as SelectionInMultipleBlocks ).blockStartId &&
+				selection1.blockEndId ===
+					( selection2 as SelectionInMultipleBlocks ).blockEndId &&
+				areCursorPositionsEqual(
+					selection1.cursorStartPosition,
+					( selection2 as SelectionInMultipleBlocks )
+						.cursorStartPosition
+				) &&
+				areCursorPositionsEqual(
+					selection1.cursorEndPosition,
+					( selection2 as SelectionInMultipleBlocks )
+						.cursorEndPosition
+				)
+			);
+		case SelectionType.WholeBlock:
+			return (
+				selection1.blockId ===
+				( selection2 as SelectionWholeBlock ).blockId
+			);
+
+		default:
+			//logger.error( 'Unable to compare selection types:', selection1, selection2 );
+			return false;
+	}
+}
+
+function areCursorPositionsEqual(
+	cursorPosition1: CursorPosition,
+	cursorPosition2: CursorPosition
+): boolean {
+	const isRelativePositionEqual =
+		JSON.stringify( cursorPosition1.relativePosition ) ===
+		JSON.stringify( cursorPosition2.relativePosition );
+
+	// Ensure a change in calculated absolute offset results in a treating the cursor as modified.
+	// This is necessary because Y.Text relative positions can remain the same after text changes.
+	const isAbsoluteOffsetEqual =
+		cursorPosition1.absoluteOffset === cursorPosition2.absoluteOffset;
+
+	return isRelativePositionEqual && isAbsoluteOffsetEqual;
+}
+
+export function areEditorStatesEqual(
+	state1?: EditorState,
+	state2?: EditorState
+): boolean {
+	if ( ! state1 || ! state2 ) {
+		return state1 === state2;
+	}
+
+	return areSelectionsEqual( state1.selection, state2.selection );
+}
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index 60378deb374e95..c815e817705db5 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -62,7 +62,10 @@ export type ProviderCreator = (
 ) => Promise< ProviderCreatorResult >;
 
 export interface RecordHandlers {
-	editRecord: ( data: Partial< ObjectData > ) => void;
+	editRecord: (
+		data: Partial< ObjectData >,
+		options?: { undoIgnore?: boolean }
+	) => void;
 	getEditedRecord: () => Promise< ObjectData >;
 	refetchRecord: () => Promise< void >;
 	saveRecord: () => Promise< void >;
diff --git a/packages/sync/src/user-utils.ts b/packages/sync/src/user-utils.ts
index 1a7a9a1ab25589..51a059a87c58ca 100644
--- a/packages/sync/src/user-utils.ts
+++ b/packages/sync/src/user-utils.ts
@@ -82,7 +82,8 @@ function generateColorVariation( hexColor: string ): string {
 	const newB = Math.min( 255, Math.max( 0, b + shift ) );
 
 	// Convert back to hex
-	const toHex = ( n: number ) => n.toString( 16 ).padStart( 2, '0' ).toUpperCase();
+	const toHex = ( n: number ) =>
+		n.toString( 16 ).padStart( 2, '0' ).toUpperCase();
 	return `#${ toHex( newR ) }${ toHex( newG ) }${ toHex( newB ) }`;
 }
 
diff --git a/packages/sync/src/utils.ts b/packages/sync/src/utils.ts
index baa9373223f27d..fcd77dc6db2661 100644
--- a/packages/sync/src/utils.ts
+++ b/packages/sync/src/utils.ts
@@ -14,7 +14,6 @@ import {
 	CRDT_STATE_VERSION_KEY,
 } from './config';
 import type { CRDTDoc } from './types';
-import type { UserInfo } from './awareness/awareness-types';
 
 // An object representation of CRDT document metadata.
 type DocumentMeta = Record< string, DocumentMetaValue >;
diff --git a/packages/sync/tsconfig.json b/packages/sync/tsconfig.json
index 3dee2350432214..b8d226845cb662 100644
--- a/packages/sync/tsconfig.json
+++ b/packages/sync/tsconfig.json
@@ -6,6 +6,8 @@
 	},
 	"exclude": [ "src/y-utilities/y-multidoc-undomanager.js" ],
 	"references": [
+		{ "path": "../block-editor" },
+		{ "path": "../data" },
 		{ "path": "../hooks" },
 		{ "path": "../undo-manager" },
 		{ "path": "../url" }

From e68cfde1c428139232e022c882a541585825ba34 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 15:13:40 +1100
Subject: [PATCH 07/30] Ensure the pckakge-lock changes are in

---
 package-lock.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package-lock.json b/package-lock.json
index 4332b25d2a11a5..0fac6a160d6c79 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -54921,6 +54921,7 @@
 			"dependencies": {
 				"@types/diff": "7.0.2",
 				"@wordpress/block-editor": "file:../block-editor",
+				"@wordpress/data": "file:../data",
 				"@wordpress/hooks": "file:../hooks",
 				"@wordpress/undo-manager": "file:../undo-manager",
 				"@wordpress/url": "file:../url",

From 77cad8f6b20c45d4170e46b7d12fe0c475a4ba42 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 15:23:49 +1100
Subject: [PATCH 08/30] Add more comments and simplify the user handling

---
 .../sync/src/awareness/awareness-manager.ts   | 17 +++++++-----
 .../sync/src/awareness/awareness-state.ts     | 26 +++++++++----------
 packages/sync/src/manager.ts                  |  6 +----
 3 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index e9b979e384a2d1..f8274769d6365d 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -6,7 +6,7 @@ import type * as Y from 'yjs';
 /**
  * Internal dependencies
  */
-import type { ObjectID, ObjectType } from '../types';
+import type { ObjectID, ObjectType, RecordHandlers } from '../types';
 import type { AwarenessState } from './awareness-state';
 import { PostEditorAwarenessState } from './post-editor-awareness-state';
 import type { UserInfo, WordPressUserInfo } from './awareness-types';
@@ -73,22 +73,25 @@ export function getPostEditorAwareness(
 
 /**
  * Create an awareness instance for the given object type and object ID.
- * @param objectType  Object type.
- * @param objectId    Object ID.
- * @param ydoc        Yjs document.
- * @param currentUser Current user.
+ * @param objectType     Object type.
+ * @param objectId       Object ID.
+ * @param ydoc           Yjs document.
+ * @param recordHandlers Record handlers.
  * @return Awareness instance.
  */
 export async function createAwareness(
 	objectType: ObjectType,
 	objectId: ObjectID | null,
 	ydoc: Y.Doc,
-	currentUser: WordPressUserInfo
+	recordHandlers: RecordHandlers
 ): Promise< AwarenessState | undefined > {
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
+
+		const currentUser = await recordHandlers.getCurrentUser();
 		const userInfo = getUserInfo( awareness, currentUser );
-		awareness.setUp( userInfo );
+
+		awareness.setUp( recordHandlers, userInfo );
 		awarenessInstances.set(
 			getAwarenessId( objectType, objectId ),
 			awareness
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 848208db6be4a9..923a2aabf3947d 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -30,8 +30,8 @@ abstract class AwarenessWithEqualityChecks<
 	 * trigger rerenders of any subscribed components.
 	 *
 	 * Equality checks are provided by the abstract `equalityFieldChecks` property.
-	 * @param field
-	 * @param value
+	 * @param field - The field to set.
+	 * @param value - The value to set.
 	 */
 	public setLocalStateField< FieldName extends string & keyof State >(
 		field: FieldName,
@@ -64,9 +64,9 @@ abstract class AwarenessWithEqualityChecks<
 
 	/**
 	 * Determine if a field value has changed using the provided equality checks.
-	 * @param field
-	 * @param value1
-	 * @param value2
+	 * @param field  - The field to check.
+	 * @param value1 - The first value to compare.
+	 * @param value2 - The second value to compare.
 	 */
 	protected isFieldEqual< FieldName extends keyof State >(
 		field: FieldName,
@@ -92,8 +92,8 @@ abstract class AwarenessWithEqualityChecks<
 	/**
 	 * Determine if two states are equal by comparing each field using the
 	 * provided equality checks.
-	 * @param state1
-	 * @param state2
+	 * @param state1 - The first state to compare.
+	 * @param state2 - The second state to compare.
 	 */
 	protected isStateEqual( state1: State, state2: State ): boolean {
 		return [
@@ -190,7 +190,7 @@ export abstract class AwarenessState<
 
 	/**
 	 * Allow external code to subscribe to awareness state changes.
-	 * @param callback
+	 * @param callback - The callback to subscribe to.
 	 */
 	public onStateChange(
 		callback: ( newState: EnhancedState< State >[] ) => void
@@ -207,9 +207,9 @@ export abstract class AwarenessState<
 	/**
 	 * Set a local state field on an awareness document with throttle. See caveats
 	 * of this.setLocalStateField.
-	 * @param field
-	 * @param value
-	 * @param wait
+	 * @param field - The field to set.
+	 * @param value - The value to set.
+	 * @param wait  - The wait time in milliseconds.
 	 */
 	public setThrottledLocalStateField<
 		FieldName extends string & keyof State,
@@ -234,7 +234,7 @@ export abstract class AwarenessState<
 
 	/**
 	 * Set the current user's connection status as awareness state.
-	 * @param isConnected
+	 * @param isConnected - The connection status.
 	 */
 	public setConnectionStatus( isConnected: boolean ): void {
 		if ( isConnected ) {
@@ -248,7 +248,7 @@ export abstract class AwarenessState<
 
 	/**
 	 * Update all subscribed listeners with the latest awareness state.
-	 * @param forceUpdate
+	 * @param forceUpdate - Whether to force an update.
 	 */
 	protected updateSubscribers( forceUpdate = false ): void {
 		if ( ! this.stateSubscriptions.length ) {
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index 4f856aad1ca66a..cb992c9f77b641 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -174,16 +174,12 @@ export function createSyncManager(): SyncManager {
 
 		entityStates.set( entityId, entityState );
 
-		// Get the current user from the handlers.
-		const currentUser = await handlers.getCurrentUser();
-
 		// Create awareness for the given entity and its Yjs document.
 		const awareness = await createAwareness(
 			objectType,
 			objectId,
 			ydoc,
-			handlers,
-			currentUser
+			handlers
 		);
 
 		// Create providers for the given entity and its Yjs document.

From 0e12107399cc42c0b7e5def2a9273724de647df3 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 15:54:29 +1100
Subject: [PATCH 09/30] Tweak the exported functions

---
 packages/sync/README.md                          | 10 ----------
 packages/sync/src/awareness/awareness-manager.ts |  4 ++++
 packages/sync/src/index.ts                       |  1 -
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/packages/sync/README.md b/packages/sync/README.md
index 8828c965b2db6e..2dd2b37cc4056c 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -50,16 +50,6 @@ Origin string for CRDT document changes originating from the local editor.
 
 Origin string for CRDT document changes originating from the sync manager.
 
-### setConnectionStatus
-
-Set the current user's connection status in the awareness instance for the given object type and object ID.
-
-_Parameters_
-
--   _objectType_ `ObjectType`: Object type.
--   _objectId_ `ObjectID | null`: Object ID.
--   _isConnected_ `boolean`: Connection status.
-
 ### WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE
 
 WordPress meta key used to persist the CRDT document for an entity.
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index f8274769d6365d..986ac2b1a2cb53 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -88,6 +88,7 @@ export async function createAwareness(
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
 
+		// TODO: Is there still a need to memoize the current user?
 		const currentUser = await recordHandlers.getCurrentUser();
 		const userInfo = getUserInfo( awareness, currentUser );
 
@@ -104,6 +105,9 @@ export async function createAwareness(
 
 /**
  * Set the current user's connection status in the awareness instance for the given object type and object ID.
+ *
+ * TODO: Use this in a generic way with each provider so it doesn't need to be exported externally.
+ *
  * @param objectType  Object type.
  * @param objectId    Object ID.
  * @param isConnected Connection status.
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 17d0c4444fb78a..13f9875c021c4c 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -28,4 +28,3 @@ export {
 } from './config';
 export { createSyncManager } from './manager';
 export type * from './types';
-export { setConnectionStatus } from './awareness/awareness-manager';

From 1b19ef1fc28fe6ea87c3788c39dbaebfccf5cc0e Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 15:58:12 +1100
Subject: [PATCH 10/30] Revert the webpack workaround

---
 packages/dependency-extraction-webpack-plugin/lib/util.js | 1 +
 packages/sync/package.json                                | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dependency-extraction-webpack-plugin/lib/util.js b/packages/dependency-extraction-webpack-plugin/lib/util.js
index ce420116404a29..5a5d88b8006ff6 100644
--- a/packages/dependency-extraction-webpack-plugin/lib/util.js
+++ b/packages/dependency-extraction-webpack-plugin/lib/util.js
@@ -5,6 +5,7 @@ const BUNDLED_PACKAGES = [
 	'@wordpress/dataviews/wp',
 	'@wordpress/icons',
 	'@wordpress/interface',
+	'@wordpress/sync',
 	'@wordpress/undo-manager',
 	'@wordpress/upload-media',
 	'@wordpress/fields',
diff --git a/packages/sync/package.json b/packages/sync/package.json
index 532b91b111bc4a..72a63f8605a302 100644
--- a/packages/sync/package.json
+++ b/packages/sync/package.json
@@ -40,7 +40,6 @@
 		"./package.json": "./package.json"
 	},
 	"react-native": "src/index",
-	"wpScript": true,
 	"types": "build-types",
 	"sideEffects": false,
 	"dependencies": {

From 215942cb19c8443103005341ef849628f25ad2ab Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 16:14:13 +1100
Subject: [PATCH 11/30] Fix the type error

---
 packages/sync/src/awareness/post-editor-awareness-state.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 8f27466ef780c6..62ae8114a53153 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -8,8 +8,6 @@ import type * as Y from 'yjs';
  */
 import { store as blockEditorStore } from '@wordpress/block-editor';
 import { select, subscribe } from '@wordpress/data';
-// @ts-expect-error No exported types for block editor store selectors.
-import { type BlockEditorStoreSelectors } from '@wordpress/block-editor/build-types/store/selectors';
 
 /**
  * Internal dependencies
@@ -51,7 +49,7 @@ export class PostEditorAwarenessState extends AwarenessState< PostEditorState >
 			getSelectionStart,
 			getSelectionEnd,
 			getSelectedBlocksInitialCaretPosition,
-		} = select( blockEditorStore ) as BlockEditorStoreSelectors;
+		} = select( blockEditorStore );
 
 		// Keep track of the current selection in the outer scope so we can compare
 		// in the subscription.

From 4f37149063f6d259c571761b71157ae3f64328da Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Mon, 19 Jan 2026 21:16:33 +1100
Subject: [PATCH 12/30] ignore types for block editor import

---
 packages/sync/src/awareness/post-editor-awareness-state.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 62ae8114a53153..9b11fe04b06b71 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -6,6 +6,7 @@ import type * as Y from 'yjs';
 /**
  * WordPress dependencies
  */
+// @ts-ignore No exported types for block editor store selectors.
 import { store as blockEditorStore } from '@wordpress/block-editor';
 import { select, subscribe } from '@wordpress/data';
 

From e9cc4bc27ae5369f96628d6758118cd4b37f0d13 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Tue, 20 Jan 2026 10:50:35 +1100
Subject: [PATCH 13/30] Fix the typo in the constant

---
 packages/sync/src/config.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/sync/src/config.ts b/packages/sync/src/config.ts
index 67bb5cf108e07a..17f65d080cebbf 100644
--- a/packages/sync/src/config.ts
+++ b/packages/sync/src/config.ts
@@ -67,7 +67,7 @@ export const REMOVAL_DELAY_IN_MS = 5000;
 /**
  * Delay in milliseconds before updating the cursor position.
  */
-export const LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS = 500;
+export const LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS = 5;
 
 /**
  * Delay in milliseconds before throttling the cursor position updates.

From 63a11d7f546cee54ab5f41ea161db76648e193c1 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Tue, 20 Jan 2026 10:55:05 +1100
Subject: [PATCH 14/30] Tweaked the local storage key

---
 packages/sync/src/user-utils.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/sync/src/user-utils.ts b/packages/sync/src/user-utils.ts
index 51a059a87c58ca..97543d08fbe48a 100644
--- a/packages/sync/src/user-utils.ts
+++ b/packages/sync/src/user-utils.ts
@@ -15,7 +15,7 @@ const COLOR_PALETTE = [
 	'#37C5F0', // cyan
 ];
 
-const LOCAL_STORAGE_KEY = 'gutenberg-rtc-preferred-color';
+const LOCAL_STORAGE_KEY = 'GUTENBERG_PREFERRED_COLOR_KEY';
 
 /**
  * Generate a random integer between min and max, inclusive.

From 71c7741fedb87f50757319bd24e5a21fa4fff85d Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Tue, 20 Jan 2026 11:07:17 +1100
Subject: [PATCH 15/30] Attempting to solve the test failures

---
 packages/core-data/src/test/resolvers.js         | 2 ++
 packages/core-data/src/utils/test/crdt-blocks.ts | 9 ++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/packages/core-data/src/test/resolvers.js b/packages/core-data/src/test/resolvers.js
index 60e56079ee9a7c..f1e66c946bd7d2 100644
--- a/packages/core-data/src/test/resolvers.js
+++ b/packages/core-data/src/test/resolvers.js
@@ -172,6 +172,7 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
+				getCurrentUser: expect.any( Function ),
 			}
 		);
 	} );
@@ -225,6 +226,7 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
+				getCurrentUser: expect.any( Function ),
 			}
 		);
 	} );
diff --git a/packages/core-data/src/utils/test/crdt-blocks.ts b/packages/core-data/src/utils/test/crdt-blocks.ts
index 27cdf7f8fd731f..bc4b91e7594eac 100644
--- a/packages/core-data/src/utils/test/crdt-blocks.ts
+++ b/packages/core-data/src/utils/test/crdt-blocks.ts
@@ -6,7 +6,14 @@ import { Y } from '@wordpress/sync';
 /**
  * External dependencies
  */
-import { describe, expect, it, jest, beforeEach } from '@jest/globals';
+import {
+	describe,
+	expect,
+	it,
+	jest,
+	beforeEach,
+	afterEach,
+} from '@jest/globals';
 
 /**
  * Mock uuid module

From f6a7cc0062c991b66130f373bd72be9b3e0480e6 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Tue, 20 Jan 2026 11:36:57 +1100
Subject: [PATCH 16/30] Fix the test fialures

---
 packages/core-data/src/utils/test/crdt-blocks.ts | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/packages/core-data/src/utils/test/crdt-blocks.ts b/packages/core-data/src/utils/test/crdt-blocks.ts
index bc4b91e7594eac..f03453c6582bac 100644
--- a/packages/core-data/src/utils/test/crdt-blocks.ts
+++ b/packages/core-data/src/utils/test/crdt-blocks.ts
@@ -19,19 +19,26 @@ import {
  * Mock uuid module
  */
 jest.mock( 'uuid', () => ( {
-	v4: jest.fn( () => 'mocked-uuid-' + Math.random() ),
+	v4: () => 'mocked-uuid-' + Math.random(),
 } ) );
 
 /**
  * Mock @wordpress/blocks module
  */
 jest.mock( '@wordpress/blocks', () => ( {
-	getBlockTypes: jest.fn( () => [
+	getBlockTypes: () => [
 		{
 			name: 'core/paragraph',
 			attributes: { content: { type: 'rich-text' } },
 		},
-	] ),
+	],
+} ) );
+
+/**
+ * Mock @wordpress/block-editor to avoid private-apis unlock errors
+ */
+jest.mock( '@wordpress/block-editor', () => ( {
+	store: {},
 } ) );
 
 /**

From 9200272507dcdfb04a2d72d70ccb0e73dd1fed47 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 07:43:57 +1100
Subject: [PATCH 17/30] Remove a TODO

---
 packages/sync/src/awareness/awareness-manager.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 986ac2b1a2cb53..33ef7f48679caf 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -88,7 +88,6 @@ export async function createAwareness(
 	if ( objectId && objectType.startsWith( 'postType/' ) ) {
 		const awareness = new PostEditorAwarenessState( ydoc );
 
-		// TODO: Is there still a need to memoize the current user?
 		const currentUser = await recordHandlers.getCurrentUser();
 		const userInfo = getUserInfo( awareness, currentUser );
 

From a2f7a09e82f841a4057dac71813a121beeec4aca Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 15:56:39 +1100
Subject: [PATCH 18/30] Re-wrote the user selection to be in the core-data, and
 move the awareness instance management to sync via getSyncanager

---
 package-lock.json                             |   3 +-
 packages/core-data/package.json               |   1 +
 packages/core-data/src/resolvers.js           |  19 +-
 .../src/utils/crdt-user-selections.ts         | 377 ++++++++++++++++++
 packages/core-data/tsconfig.json              |   3 +-
 packages/sync/README.md                       |   4 +
 packages/sync/package.json                    |   2 -
 .../sync/src/awareness/awareness-manager.ts   |  60 ---
 .../awareness/post-editor-awareness-state.ts  | 114 +-----
 packages/sync/src/index.ts                    |   1 +
 packages/sync/src/manager.ts                  |  47 ++-
 packages/sync/src/selection-utils.ts          | 221 ++--------
 packages/sync/src/test/manager.ts             |   1 +
 packages/sync/src/types.ts                    |   5 +
 packages/sync/tsconfig.json                   |   2 -
 15 files changed, 498 insertions(+), 362 deletions(-)
 create mode 100644 packages/core-data/src/utils/crdt-user-selections.ts

diff --git a/package-lock.json b/package-lock.json
index 0b15680424cd22..16ae2a12d280ee 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -52648,6 +52648,7 @@
 				"uuid": "^9.0.1"
 			},
 			"devDependencies": {
+				"@types/node": "^20.17.10",
 				"deep-freeze": "0.0.1"
 			},
 			"engines": {
@@ -54918,8 +54919,6 @@
 			"license": "GPL-2.0-or-later",
 			"dependencies": {
 				"@types/diff": "7.0.2",
-				"@wordpress/block-editor": "file:../block-editor",
-				"@wordpress/data": "file:../data",
 				"@wordpress/hooks": "file:../hooks",
 				"@wordpress/undo-manager": "file:../undo-manager",
 				"@wordpress/url": "file:../url",
diff --git a/packages/core-data/package.json b/packages/core-data/package.json
index d69644da3a2c42..cb61cd4861e0df 100644
--- a/packages/core-data/package.json
+++ b/packages/core-data/package.json
@@ -72,6 +72,7 @@
 		"uuid": "^9.0.1"
 	},
 	"devDependencies": {
+		"@types/node": "^20.17.10",
 		"deep-freeze": "0.0.1"
 	},
 	"peerDependencies": {
diff --git a/packages/core-data/src/resolvers.js b/packages/core-data/src/resolvers.js
index c990c2ad226f72..0d68f5166e23a2 100644
--- a/packages/core-data/src/resolvers.js
+++ b/packages/core-data/src/resolvers.js
@@ -26,6 +26,7 @@ import {
 	isNumericID,
 } from './utils';
 import { fetchBlockPatterns } from './fetch';
+import { subscribeToUserSelectionChanges } from './utils/crdt-user-selections';
 
 /**
  * Requests authors from the REST API.
@@ -234,8 +235,22 @@ export const getEntityRecord =
 								);
 							},
 							// Get the current user.
-							getCurrentUser: async () =>
-								await resolveSelect.getCurrentUser(),
+							getCurrentUser: async () => {
+								await resolveSelect.getCurrentUser();
+							},
+							// Subscribe to user selection changes.
+							subscribeToUserSelectionChanges: (
+								yDoc,
+								setSelectionState
+							) => {
+								subscribeToUserSelectionChanges(
+									kind,
+									name,
+									key,
+									yDoc,
+									setSelectionState
+								);
+							},
 						}
 					);
 				}
diff --git a/packages/core-data/src/utils/crdt-user-selections.ts b/packages/core-data/src/utils/crdt-user-selections.ts
new file mode 100644
index 00000000000000..f2cad5437089e8
--- /dev/null
+++ b/packages/core-data/src/utils/crdt-user-selections.ts
@@ -0,0 +1,377 @@
+/**
+ * WordPress dependencies
+ */
+import { dispatch, select, subscribe } from '@wordpress/data';
+import {
+	Y,
+	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
+	CRDT_RECORD_MAP_KEY,
+} from '@wordpress/sync';
+// @ts-ignore No exported types for block editor store selectors.
+import { store as blockEditorStore } from '@wordpress/block-editor';
+
+/**
+ * Internal dependencies
+ */
+import { store as coreStore } from '../';
+import { type WPBlockSelection } from '../types';
+
+/**
+ * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
+ */
+type BlockClientId = string;
+type BlockInnerBlocks = Y.Array< SelectableBlock >;
+type BlockAttributes = Y.Map< Y.Text >;
+
+/**
+ * A block that can be selected.
+ */
+export type SelectableBlock = Y.Map<
+	BlockClientId | BlockAttributes | BlockInnerBlocks
+>;
+
+/**
+ * The type of selection.
+ */
+export enum SelectionType {
+	None = 'none',
+	Cursor = 'cursor',
+	SelectionInOneBlock = 'selection-in-one-block',
+	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
+	WholeBlock = 'whole-block',
+}
+
+/**
+ * The position of the cursor.
+ */
+export type CursorPosition = {
+	relativePosition: Y.RelativePosition;
+
+	// Also store the absolute offset index of the cursor from the perspective
+	// of the user who is updating the selection.
+	//
+	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
+	// on relativePosition for the most up-to-date positioning.
+	//
+	// This is used because local Y.Text changes (e.g. adding or deleting a character)
+	// can result in the same relative position if it is pinned to an unchanged
+	// character. With both of these values as editor state, a change in perceived
+	// position will always result in a redraw.
+	absoluteOffset: number;
+};
+
+export type SelectionNone = {
+	// The user has not made a selection.
+	type: SelectionType.None;
+};
+
+export type SelectionCursor = {
+	// The user has a cursor position in a block with no text highlighted.
+	type: SelectionType.Cursor;
+	blockId: string;
+	cursorPosition: CursorPosition;
+};
+
+export type SelectionInOneBlock = {
+	// The user has highlighted text in a single block.
+	type: SelectionType.SelectionInOneBlock;
+	blockId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionInMultipleBlocks = {
+	// The user has highlighted text over multiple blocks.
+	type: SelectionType.SelectionInMultipleBlocks;
+	blockStartId: string;
+	blockEndId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionWholeBlock = {
+	// The user has a non-text block selected, like an image block.
+	type: SelectionType.WholeBlock;
+	blockId: string;
+};
+
+export type SelectionState =
+	| SelectionNone
+	| SelectionCursor
+	| SelectionInOneBlock
+	| SelectionInMultipleBlocks
+	| SelectionWholeBlock;
+
+/**
+ * Subscribe to user selection changes and update the selection state.
+ *
+ * @param kind              - The kind of entity.
+ * @param name              - The name of the entity.
+ * @param recordId          - The ID of the entity.
+ * @param yDoc              - Y.Doc
+ * @param setSelectionState - The function to set the selection state.
+ */
+export function subscribeToUserSelectionChanges(
+	kind: string,
+	name: string,
+	recordId: string | number,
+	yDoc: Y.Doc,
+	setSelectionState: ( selectionState: SelectionState ) => void
+): void {
+	const {
+		getSelectionStart,
+		getSelectionEnd,
+		getSelectedBlocksInitialCaretPosition,
+	} = select( blockEditorStore );
+
+	// Keep track of the current selection in the outer scope so we can compare
+	// in the subscription.
+	let selectionStart = getSelectionStart();
+	let selectionEnd = getSelectionEnd();
+	let localCursorTimeout: NodeJS.Timeout | null = null;
+
+	subscribe( () => {
+		const newSelectionStart = getSelectionStart();
+		const newSelectionEnd = getSelectionEnd();
+
+		if (
+			newSelectionStart === selectionStart &&
+			newSelectionEnd === selectionEnd
+		) {
+			return;
+		}
+
+		selectionStart = newSelectionStart;
+		selectionEnd = newSelectionEnd;
+
+		// Typically selection position is only persisted after typing in a block, which
+		// can cause selection position to be reset by other users making block updates.
+		// Ensure we update the controlled selection right away, persisting our cursor position locally.
+		const initialPosition = getSelectedBlocksInitialCaretPosition();
+		void updateSelectionInEntityRecord(
+			kind,
+			name,
+			recordId,
+			selectionStart,
+			selectionEnd,
+			initialPosition
+		);
+
+		// We receive two selection changes in quick succession
+		// from local selection events:
+		//   { clientId: "123...", attributeKey: "content", offset: undefined }
+		//   { clientId: "123...", attributeKey: "content", offset: 554 }
+		// Add a short debounce to avoid sending the first selection change.
+		if ( localCursorTimeout ) {
+			clearTimeout( localCursorTimeout );
+		}
+
+		localCursorTimeout = setTimeout( () => {
+			const selectionState = getSelectionState(
+				selectionStart,
+				selectionEnd,
+				yDoc
+			);
+			setSelectionState( selectionState );
+		}, LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS );
+	} );
+}
+
+/**
+ * Converts WordPress block editor selection to a SelectionState.
+ *
+ * @param selectionStart - The start position of the selection
+ * @param selectionEnd   - The end position of the selection
+ * @param yDoc           - The Yjs document
+ * @return The SelectionState
+ */
+function getSelectionState(
+	selectionStart: WPBlockSelection,
+	selectionEnd: WPBlockSelection,
+	yDoc: Y.Doc
+): SelectionState {
+	const ydoc = yDoc.getMap( CRDT_RECORD_MAP_KEY );
+	const yBlocks = ydoc.get( 'blocks' ) as Y.Array< SelectableBlock >;
+
+	const isSelectionEmpty = Object.keys( selectionStart ).length === 0;
+	const noSelection: SelectionNone = {
+		type: SelectionType.None,
+	};
+
+	if ( isSelectionEmpty ) {
+		// Case 1: No selection
+		return noSelection;
+	}
+
+	// When the page initially loads, selectionStart can contain an empty object `{}`.
+	const isSelectionInOneBlock =
+		selectionStart.clientId === selectionEnd.clientId;
+	const isCursorOnly =
+		isSelectionInOneBlock && selectionStart.offset === selectionEnd.offset;
+	const isSelectionAWholeBlock =
+		isSelectionInOneBlock &&
+		selectionStart.offset === undefined &&
+		selectionEnd.offset === undefined;
+
+	if ( isSelectionAWholeBlock ) {
+		// Case 2: A whole block is selected.
+		return {
+			type: SelectionType.WholeBlock,
+			blockId: selectionStart.clientId,
+		};
+	} else if ( isCursorOnly ) {
+		// Case 3: Cursor only, no text selected
+		const cursorPosition = getCursorPosition( selectionStart, yBlocks );
+
+		if ( ! cursorPosition ) {
+			// If we can't find the cursor position in block text, treat it as a non-selection.
+			return noSelection;
+		}
+
+		return {
+			type: SelectionType.Cursor,
+			blockId: selectionStart.clientId,
+			cursorPosition,
+		};
+	} else if ( isSelectionInOneBlock ) {
+		// Case 4: Selection in a single block
+		const cursorStartPosition = getCursorPosition(
+			selectionStart,
+			yBlocks
+		);
+		const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
+
+		if ( ! cursorStartPosition || ! cursorEndPosition ) {
+			// If we can't find the cursor positions in block text, treat it as a non-selection.
+			return noSelection;
+		}
+
+		return {
+			type: SelectionType.SelectionInOneBlock,
+			blockId: selectionStart.clientId,
+			cursorStartPosition,
+			cursorEndPosition,
+		};
+	}
+
+	// Caes 5: Selection in multiple blocks
+	const cursorStartPosition = getCursorPosition( selectionStart, yBlocks );
+	const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
+	if ( ! cursorStartPosition || ! cursorEndPosition ) {
+		// If we can't find the cursor positions in block text, treat it as a non-selection.
+		return noSelection;
+	}
+
+	return {
+		type: SelectionType.SelectionInMultipleBlocks,
+		blockStartId: selectionStart.clientId,
+		blockEndId: selectionEnd.clientId,
+		cursorStartPosition,
+		cursorEndPosition,
+	};
+}
+
+/**
+ * Update the entity record with the current user's selection.
+ *
+ * @param kind            - The kind of entity.
+ * @param name            - The name of the entity.
+ * @param recordId        - The ID of the entity.
+ * @param selectionStart  - The start position of the selection.
+ * @param selectionEnd    - The end position of the selection.
+ * @param initialPosition - The initial position of the selection.
+ */
+export async function updateSelectionInEntityRecord(
+	kind: string,
+	name: string,
+	recordId: string | number,
+	selectionStart: WPBlockSelection,
+	selectionEnd: WPBlockSelection,
+	initialPosition: number | null
+): Promise< void > {
+	if ( ! selectionStart.clientId ) {
+		return;
+	}
+
+	// Send an entityRecord `selection` update if we have a selection.
+	//
+	// Normally WordPress updates the `selection` property of the post when changes are made to blocks.
+	// In a multi-user setup, block changes can occur from other users. When an entity is updated from another
+	// user's changes, useBlockSync() in Gutenberg will reset the user's selection to the last saved selection.
+	//
+	// Manually adding an edit for each movement ensures that other user's changes to the document will
+	// not cause the local user's selection to reset to the last local change location.
+	const edits = {
+		selection: { selectionStart, selectionEnd, initialPosition },
+	};
+
+	const options = {
+		undoIgnore: true,
+	};
+	const { editEntityRecord } = dispatch( coreStore );
+
+	editEntityRecord( kind, name, recordId, edits, options );
+}
+
+/**
+ * Get the cursor position from a selection.
+ *
+ * @param selection - The selection.
+ * @param blocks    - The blocks to search through.
+ * @return The cursor position, or null if not found.
+ */
+function getCursorPosition(
+	selection: WPBlockSelection,
+	blocks: Y.Array< SelectableBlock >
+): CursorPosition | null {
+	const block = findBlockByClientId( selection.clientId, blocks );
+	if ( ! block ) {
+		return null;
+	}
+
+	const attributes = block.get( 'attributes' ) as Y.Map< Y.Text >;
+	const currentYText = attributes.get( selection.attributeKey ) as Y.Text;
+
+	const relativePosition = Y.createRelativePositionFromTypeIndex(
+		currentYText,
+		selection.offset
+	);
+
+	return {
+		relativePosition,
+		absoluteOffset: selection.offset,
+	};
+}
+
+/**
+ * Find a block by its client ID.
+ *
+ * @param blockId - The client ID of the block.
+ * @param blocks  - The blocks to search through.
+ * @return The block if found, null otherwise.
+ */
+function findBlockByClientId(
+	blockId: string,
+	blocks: Y.Array< SelectableBlock >
+): SelectableBlock | null {
+	for ( const block of blocks ) {
+		if ( block.get( 'clientId' ) === blockId ) {
+			return block;
+		}
+
+		const innerBlocks = block.get( 'innerBlocks' ) as BlockInnerBlocks;
+
+		if ( innerBlocks.length > 0 ) {
+			const innerBlock = findBlockByClientId(
+				blockId,
+				block.get( 'innerBlocks' ) as Y.Array< SelectableBlock >
+			);
+
+			if ( innerBlock ) {
+				return innerBlock;
+			}
+		}
+	}
+
+	return null;
+}
diff --git a/packages/core-data/tsconfig.json b/packages/core-data/tsconfig.json
index 57c9d208e4c689..f392810314f200 100644
--- a/packages/core-data/tsconfig.json
+++ b/packages/core-data/tsconfig.json
@@ -3,7 +3,8 @@
 	"extends": "../../tsconfig.base.json",
 	"compilerOptions": {
 		"checkJs": false,
-		"noImplicitAny": false
+		"noImplicitAny": false,
+		"types": [ "node" ]
 	},
 	"references": [
 		{ "path": "../api-fetch" },
diff --git a/packages/sync/README.md b/packages/sync/README.md
index 2dd2b37cc4056c..4041ab010d5772 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -42,6 +42,10 @@ The sync manager orchestrates the lifecycle of syncing entity records. It create
 
 Deltas are used to calculate incremental Y.Text updates.
 
+### LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS
+
+Delay in milliseconds before updating the cursor position.
+
 ### LOCAL_EDITOR_ORIGIN
 
 Origin string for CRDT document changes originating from the local editor.
diff --git a/packages/sync/package.json b/packages/sync/package.json
index 72a63f8605a302..592cc5a86c1d4c 100644
--- a/packages/sync/package.json
+++ b/packages/sync/package.json
@@ -44,8 +44,6 @@
 	"sideEffects": false,
 	"dependencies": {
 		"@types/diff": "7.0.2",
-		"@wordpress/block-editor": "file:../block-editor",
-		"@wordpress/data": "file:../data",
 		"@wordpress/hooks": "file:../hooks",
 		"@wordpress/undo-manager": "file:../undo-manager",
 		"@wordpress/url": "file:../url",
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
index 33ef7f48679caf..625b61b6d64195 100644
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ b/packages/sync/src/awareness/awareness-manager.ts
@@ -12,22 +12,6 @@ import { PostEditorAwarenessState } from './post-editor-awareness-state';
 import type { UserInfo, WordPressUserInfo } from './awareness-types';
 import { getBrowserName, getNewUserColor } from '../user-utils';
 
-const awarenessInstances: Map< string, AwarenessState > = new Map();
-
-function getAwarenessId(
-	objectType: ObjectType,
-	objectId: ObjectID | null
-): string {
-	return `${ objectType }:${ objectId }`;
-}
-
-function getAwarenessInstance(
-	objectType: ObjectType,
-	objectId: ObjectID | null
-): AwarenessState | undefined {
-	return awarenessInstances.get( getAwarenessId( objectType, objectId ) );
-}
-
 function getUserInfo(
 	awareness: AwarenessState,
 	wpUser: WordPressUserInfo
@@ -50,27 +34,6 @@ function getUserInfo(
 	};
 }
 
-/**
- * Get the post editor awareness instance for the given post ID and post type.
- * @param postId   Post ID.
- * @param postType Post type.
- * @return Post editor awareness instance.
- */
-export function getPostEditorAwareness(
-	postId: number,
-	postType: string
-): PostEditorAwarenessState | undefined {
-	const objectId: ObjectID = postId.toString();
-	const objectType: ObjectType = `postType/${ postType }`;
-
-	const awareness = getAwarenessInstance( objectType, objectId );
-	if ( awareness instanceof PostEditorAwarenessState ) {
-		return awareness;
-	}
-
-	return undefined;
-}
-
 /**
  * Create an awareness instance for the given object type and object ID.
  * @param objectType     Object type.
@@ -92,31 +55,8 @@ export async function createAwareness(
 		const userInfo = getUserInfo( awareness, currentUser );
 
 		awareness.setUp( recordHandlers, userInfo );
-		awarenessInstances.set(
-			getAwarenessId( objectType, objectId ),
-			awareness
-		);
 
 		return awareness;
 	}
 	return undefined;
 }
-
-/**
- * Set the current user's connection status in the awareness instance for the given object type and object ID.
- *
- * TODO: Use this in a generic way with each provider so it doesn't need to be exported externally.
- *
- * @param objectType  Object type.
- * @param objectId    Object ID.
- * @param isConnected Connection status.
- */
-export function setConnectionStatus(
-	objectType: ObjectType,
-	objectId: ObjectID | null,
-	isConnected: boolean
-): void {
-	getAwarenessInstance( objectType, objectId )?.setConnectionStatus(
-		isConnected
-	);
-}
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
index 9b11fe04b06b71..8e6e551d0ebbd1 100644
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ b/packages/sync/src/awareness/post-editor-awareness-state.ts
@@ -1,37 +1,12 @@
-/**
- * External dependencies
- */
-import type * as Y from 'yjs';
-
-/**
- * WordPress dependencies
- */
-// @ts-ignore No exported types for block editor store selectors.
-import { store as blockEditorStore } from '@wordpress/block-editor';
-import { select, subscribe } from '@wordpress/data';
-
 /**
  * Internal dependencies
  */
-import type {
-	PostEditorState,
-	UserInfo,
-	WPBlockSelection,
-} from './awareness-types';
+import type { PostEditorState, UserInfo } from './awareness-types';
 import type { RecordHandlers } from '../types';
 import { AwarenessState } from './awareness-state';
 import { areUserInfosEqual } from '../user-utils';
-import {
-	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
-	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
-	CRDT_RECORD_MAP_KEY,
-} from '../config';
-import type { SelectableBlock } from '../selection-utils';
-import {
-	updateSelectionInEntityRecord,
-	getSelectionState,
-	areEditorStatesEqual,
-} from '../selection-utils';
+import { AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS } from '../config';
+import { areEditorStatesEqual } from '../selection-utils';
 
 export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
 	protected equalityFieldChecks = {
@@ -42,80 +17,15 @@ export class PostEditorAwarenessState extends AwarenessState< PostEditorState >
 	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
 		super.setUp( recordHandlers, userInfo );
 
-		this.subscribeToSelectionChanges( recordHandlers );
-	}
-
-	private subscribeToSelectionChanges( handlers: RecordHandlers ): void {
-		const {
-			getSelectionStart,
-			getSelectionEnd,
-			getSelectedBlocksInitialCaretPosition,
-		} = select( blockEditorStore );
-
-		// Keep track of the current selection in the outer scope so we can compare
-		// in the subscription.
-		let selectionStart = getSelectionStart();
-		let selectionEnd = getSelectionEnd();
-		let localCursorTimeout: NodeJS.Timeout | null = null;
-
-		// Provided type is generic `Function`.
-
-		subscribe( () => {
-			const newSelectionStart = getSelectionStart();
-			const newSelectionEnd = getSelectionEnd();
-
-			if (
-				newSelectionStart === selectionStart &&
-				newSelectionEnd === selectionEnd
-			) {
-				return;
-			}
-
-			selectionStart = newSelectionStart;
-			selectionEnd = newSelectionEnd;
-
-			// Typically selection position is only persisted after typing in a block, which
-			// can cause selection position to be reset by other users making block updates.
-			// Ensure we update the controlled selection right away, persisting our cursor position locally.
-			void updateSelectionInEntityRecord(
-				handlers,
-				selectionStart,
-				selectionEnd,
-				getSelectedBlocksInitialCaretPosition()
-			);
-
-			// We receive two selection changes in quick succession
-			// from local selection events:
-			//   { clientId: "123...", attributeKey: "content", offset: undefined }
-			//   { clientId: "123...", attributeKey: "content", offset: 554 }
-			// Add a short debounce to avoid sending the first selection change.
-			if ( localCursorTimeout ) {
-				clearTimeout( localCursorTimeout );
-			}
-
-			localCursorTimeout = setTimeout( () => {
-				this.updateSelectionState( selectionStart, selectionEnd );
-			}, LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS );
-		} );
-	}
-
-	private updateSelectionState(
-		selectionStart: WPBlockSelection,
-		selectionEnd: WPBlockSelection
-	): void {
-		const ydoc = this.doc.getMap( CRDT_RECORD_MAP_KEY );
-		const yBlocks = ydoc.get( 'blocks' ) as Y.Array< SelectableBlock >;
-		const selection = getSelectionState(
-			selectionStart,
-			selectionEnd,
-			yBlocks
-		);
-
-		// Throttle remote awareness updates.
-		this.setThrottledLocalStateField(
-			'editorState',
-			{ selection },
-			AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
+		// Subscribe to user selection changes.
+		recordHandlers.subscribeToUserSelectionChanges(
+			this.doc,
+			( selectionState ) =>
+				this.setThrottledLocalStateField(
+					'editorState',
+					{ selection: selectionState },
+					AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
+				)
 		);
 	}
 }
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 13f9875c021c4c..6180aaa8e754e3 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -25,6 +25,7 @@ export {
 	LOCAL_EDITOR_ORIGIN,
 	LOCAL_SYNC_MANAGER_ORIGIN,
 	WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE,
+	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
 } from './config';
 export { createSyncManager } from './manager';
 export type * from './types';
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index 0975b1257b63bf..5d4b7bd08aabc5 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -29,6 +29,10 @@ import type {
 import { createUndoManager } from './undo-manager';
 import { createYjsDoc } from './utils';
 import { createAwareness } from './awareness/awareness-manager';
+import type { AwarenessState } from './awareness/awareness-state';
+
+const AWARENESS_INSTANCE_SEPARATOR = ':';
+const ENTITY_INSTANCE_SEPARATOR = '_';
 
 interface EntityState {
 	handlers: RecordHandlers;
@@ -46,6 +50,7 @@ interface EntityState {
  */
 export function createSyncManager(): SyncManager {
 	const entityStates: Map< EntityID, EntityState > = new Map();
+	const awarenessInstances: Map< string, AwarenessState > = new Map();
 
 	/**
 	 * A "sync-aware" undo manager for all synced entities. It is lazily created
@@ -106,6 +111,8 @@ export function createSyncManager(): SyncManager {
 			return; // Already bootstrapped.
 		}
 
+		const awarenessId = getAwarenessId( objectType, objectId );
+
 		const ydoc = createYjsDoc( { objectType } );
 		const recordMap = ydoc.getMap( RECORD_KEY );
 		const recordMetaMap = ydoc.getMap( RECORD_METADATA_KEY );
@@ -117,6 +124,7 @@ export function createSyncManager(): SyncManager {
 			recordMap.unobserveDeep( onRecordUpdate );
 			ydoc.destroy();
 			entityStates.delete( entityId );
+			awarenessInstances.delete( awarenessId );
 		};
 
 		// When the CRDT document is updated by an UndoManager or a connection (not
@@ -182,6 +190,11 @@ export function createSyncManager(): SyncManager {
 			handlers
 		);
 
+		// Awareness can be undefined, if the object type is not supported.
+		if ( awareness ) {
+			awarenessInstances.set( awarenessId, awareness );
+		}
+
 		// Create providers for the given entity and its Yjs document.
 		const providerResults = await Promise.all(
 			providerCreators.map( ( create ) =>
@@ -217,7 +230,39 @@ export function createSyncManager(): SyncManager {
 		objectType: ObjectType,
 		objectId: ObjectID
 	): EntityID {
-		return `${ objectType }_${ objectId }`;
+		return getInstanceId( objectType, objectId, ENTITY_INSTANCE_SEPARATOR );
+	}
+
+	/**
+	 * Get the awareness ID for the given object type and object ID.
+	 *
+	 * @param {ObjectType} objectType Object type.
+	 * @param {ObjectID}   objectId   Object ID.
+	 */
+	function getAwarenessId(
+		objectType: ObjectType,
+		objectId: ObjectID
+	): string {
+		return getInstanceId(
+			objectType,
+			objectId,
+			AWARENESS_INSTANCE_SEPARATOR
+		);
+	}
+
+	/**
+	 * Get the instance ID for the given object type and object ID.
+	 *
+	 * @param {ObjectType} objectType Object type.
+	 * @param {ObjectID}   objectId   Object ID.
+	 * @param {string}     separator  Separator between object type and object ID.
+	 */
+	function getInstanceId(
+		objectType: ObjectType,
+		objectId: ObjectID,
+		separator: string
+	): string {
+		return `${ objectType }${ separator }${ objectId }`;
 	}
 
 	/**
diff --git a/packages/sync/src/selection-utils.ts b/packages/sync/src/selection-utils.ts
index 51a70a73fa5d62..520fc7b8335597 100644
--- a/packages/sync/src/selection-utils.ts
+++ b/packages/sync/src/selection-utils.ts
@@ -1,14 +1,12 @@
 /**
  * External dependencies
  */
-import * as Y from 'yjs';
+import type * as Y from 'yjs';
 
 /**
  * Internal dependencies
  */
 import type { EditorState } from './awareness/awareness-types';
-import { type WPBlockSelection } from './awareness/awareness-types';
-import type { RecordHandlers } from './types';
 
 /**
  * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
@@ -97,183 +95,13 @@ export type SelectionState =
 	| SelectionWholeBlock;
 
 /**
- * Converts WordPress block editor selection to a SelectionState.
+ * Check if two selection states are equal.
  *
- * @param selectionStart - The start position of the selection
- * @param selectionEnd   - The end position of the selection
- * @param yBlocks
- * @return The SelectionState
+ * @param selection1 - The first selection state.
+ * @param selection2 - The second selection state.
+ * @return True if the selection states are equal, false otherwise.
  */
-export function getSelectionState(
-	selectionStart: WPBlockSelection,
-	selectionEnd: WPBlockSelection,
-	yBlocks: Y.Array< SelectableBlock >
-): SelectionState {
-	const isSelectionEmpty = Object.keys( selectionStart ).length === 0;
-	const noSelection: SelectionNone = {
-		type: SelectionType.None,
-	};
-
-	if ( isSelectionEmpty ) {
-		// Case 1: No selection
-		return noSelection;
-	}
-
-	// When the page initially loads, selectionStart can contain an empty object `{}`.
-	const isSelectionInOneBlock =
-		selectionStart.clientId === selectionEnd.clientId;
-	const isCursorOnly =
-		isSelectionInOneBlock && selectionStart.offset === selectionEnd.offset;
-	const isSelectionAWholeBlock =
-		isSelectionInOneBlock &&
-		selectionStart.offset === undefined &&
-		selectionEnd.offset === undefined;
-
-	if ( isSelectionAWholeBlock ) {
-		// Case 2: A whole block is selected.
-		return {
-			type: SelectionType.WholeBlock,
-			blockId: selectionStart.clientId,
-		};
-	} else if ( isCursorOnly ) {
-		// Case 3: Cursor only, no text selected
-		const cursorPosition = getCursorPosition( selectionStart, yBlocks );
-
-		if ( ! cursorPosition ) {
-			// If we can't find the cursor position in block text, treat it as a non-selection.
-			return noSelection;
-		}
-
-		return {
-			type: SelectionType.Cursor,
-			blockId: selectionStart.clientId,
-			cursorPosition,
-		};
-	} else if ( isSelectionInOneBlock ) {
-		// Case 4: Selection in a single block
-		const cursorStartPosition = getCursorPosition(
-			selectionStart,
-			yBlocks
-		);
-		const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
-
-		if ( ! cursorStartPosition || ! cursorEndPosition ) {
-			// If we can't find the cursor positions in block text, treat it as a non-selection.
-			return noSelection;
-		}
-
-		return {
-			type: SelectionType.SelectionInOneBlock,
-			blockId: selectionStart.clientId,
-			cursorStartPosition,
-			cursorEndPosition,
-		};
-	}
-
-	// Caes 5: Selection in multiple blocks
-	const cursorStartPosition = getCursorPosition( selectionStart, yBlocks );
-	const cursorEndPosition = getCursorPosition( selectionEnd, yBlocks );
-	if ( ! cursorStartPosition || ! cursorEndPosition ) {
-		// If we can't find the cursor positions in block text, treat it as a non-selection.
-		return noSelection;
-	}
-
-	return {
-		type: SelectionType.SelectionInMultipleBlocks,
-		blockStartId: selectionStart.clientId,
-		blockEndId: selectionEnd.clientId,
-		cursorStartPosition,
-		cursorEndPosition,
-	};
-}
-
-/**
- * Update the entity record with the current user's selection.
- *
- * @param handlers        - Record handlers.
- * @param selectionStart  - The start position of the selection.
- * @param selectionEnd    - The end position of the selection.
- * @param initialPosition - The initial position of the selection.
- */
-export async function updateSelectionInEntityRecord(
-	handlers: RecordHandlers,
-	selectionStart: WPBlockSelection,
-	selectionEnd: WPBlockSelection,
-	initialPosition: number | null
-): Promise< void > {
-	if ( ! selectionStart.clientId ) {
-		return;
-	}
-
-	// Send an entityRecord `selection` update if we have a selection.
-	//
-	// Normally WordPress updates the `selection` property of the post when changes are made to blocks.
-	// In a multi-user setup, block changes can occur from other users. When an entity is updated from another
-	// user's changes, useBlockSync() in Gutenberg will reset the user's selection to the last saved selection.
-	//
-	// Manually adding an edit for each movement ensures that other user's changes to the document will
-	// not cause the local user's selection to reset to the last local change location.
-	const edits = {
-		selection: { selectionStart, selectionEnd, initialPosition },
-	};
-
-	const options = {
-		undoIgnore: true,
-	};
-
-	handlers.editRecord( edits, options );
-}
-
-export function getCursorPosition(
-	selection: WPBlockSelection,
-	blocks: Y.Array< SelectableBlock >
-): CursorPosition | null {
-	const block = findBlockByClientId( selection.clientId, blocks );
-	if ( ! block ) {
-		return null;
-	}
-
-	const attributes = block.get( 'attributes' ) as Y.Map< Y.Text >;
-	const currentYText = attributes.get( selection.attributeKey ) as Y.Text;
-
-	const relativePosition = Y.createRelativePositionFromTypeIndex(
-		currentYText,
-		selection.offset
-	);
-
-	return {
-		relativePosition,
-		absoluteOffset: selection.offset,
-	};
-}
-
-function findBlockByClientId(
-	blockId: string,
-	blocks: Y.Array< SelectableBlock >
-): SelectableBlock | null {
-	for ( const block of blocks ) {
-		if ( block.get( 'clientId' ) === blockId ) {
-			return block;
-		}
-
-		const innerBlocks = block.get( 'innerBlocks' ) as BlockInnerBlocks;
-
-		if ( innerBlocks.length > 0 ) {
-			const innerBlock = findBlockByClientId(
-				blockId,
-				block.get( 'innerBlocks' ) as Y.Array< SelectableBlock >
-			);
-
-			if ( innerBlock ) {
-				return innerBlock;
-			}
-		}
-	}
-
-	return null;
-}
-
-export function areSelectionsEqual(
+function areSelectionsEqual(
 	selection1: SelectionState,
 	selection2: SelectionState
 ): boolean {
@@ -333,11 +161,35 @@ export function areSelectionsEqual(
 			);
 
 		default:
-			//logger.error( 'Unable to compare selection types:', selection1, selection2 );
 			return false;
 	}
 }
 
+/**
+ * Check if two editor states are equal.
+ *
+ * @param state1 - The first editor state.
+ * @param state2 - The second editor state.
+ * @return True if the editor states are equal, false otherwise.
+ */
+export function areEditorStatesEqual(
+	state1?: EditorState,
+	state2?: EditorState
+): boolean {
+	if ( ! state1 || ! state2 ) {
+		return state1 === state2;
+	}
+
+	return areSelectionsEqual( state1.selection, state2.selection );
+}
+
+/**
+ * Check if two cursor positions are equal.
+ *
+ * @param cursorPosition1 - The first cursor position.
+ * @param cursorPosition2 - The second cursor position.
+ * @return True if the cursor positions are equal, false otherwise.
+ */
 function areCursorPositionsEqual(
 	cursorPosition1: CursorPosition,
 	cursorPosition2: CursorPosition
@@ -353,14 +205,3 @@ function areCursorPositionsEqual(
 
 	return isRelativePositionEqual && isAbsoluteOffsetEqual;
 }
-
-export function areEditorStatesEqual(
-	state1?: EditorState,
-	state2?: EditorState
-): boolean {
-	if ( ! state1 || ! state2 ) {
-		return state1 === state2;
-	}
-
-	return areSelectionsEqual( state1.selection, state2.selection );
-}
diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index f0a5ca0d42008f..a16b64ecc06234 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -108,6 +108,7 @@ describe( 'SyncManager', () => {
 			getCurrentUser: jest.fn( async () =>
 				Promise.resolve( mockCurrentUser )
 			),
+			subscribeToUserSelectionChanges: jest.fn(),
 		};
 	} );
 
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index c815e817705db5..b1cf0ce3660f01 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -14,6 +14,7 @@ import type { Awareness } from 'y-protocols/awareness';
  */
 import type { WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE } from './config';
 import type { WordPressUserInfo } from './awareness/awareness-types';
+import type { SelectionState } from './selection-utils';
 
 /* globalThis */
 declare global {
@@ -70,6 +71,10 @@ export interface RecordHandlers {
 	refetchRecord: () => Promise< void >;
 	saveRecord: () => Promise< void >;
 	getCurrentUser: () => Promise< WordPressUserInfo >;
+	subscribeToUserSelectionChanges: (
+		yDoc: Y.Doc,
+		setSelectionState: ( selectionState: SelectionState ) => void
+	) => void;
 }
 
 export interface SyncConfig {
diff --git a/packages/sync/tsconfig.json b/packages/sync/tsconfig.json
index b8d226845cb662..3dee2350432214 100644
--- a/packages/sync/tsconfig.json
+++ b/packages/sync/tsconfig.json
@@ -6,8 +6,6 @@
 	},
 	"exclude": [ "src/y-utilities/y-multidoc-undomanager.js" ],
 	"references": [
-		{ "path": "../block-editor" },
-		{ "path": "../data" },
 		{ "path": "../hooks" },
 		{ "path": "../undo-manager" },
 		{ "path": "../url" }

From d1066e9b1ac282b78bfccdbe7f82bb1574d394a6 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 16:10:52 +1100
Subject: [PATCH 19/30] Clean up the code

---
 .../sync/src/awareness/awareness-types.ts     | 22 -------------
 packages/sync/src/manager.ts                  | 31 +++----------------
 packages/sync/src/types.ts                    |  1 +
 3 files changed, 6 insertions(+), 48 deletions(-)

diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index ce041c73549327..3ed2ea929d9500 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -82,28 +82,6 @@ export type EnhancedState< State extends BaseState > = State & {
 	isMe: boolean;
 };
 
-/**
- * A block selection object.
- *
- * In order to avoid circular dependencies, we define it here instead of importing
- * the WPBlockSelection interface from @wordpress/editor.
- */
-export type WPBlockSelection = {
-	/**
-	 * A block client ID.
-	 */
-	clientId: string;
-	/**
-	 * A block attribute key.
-	 */
-	attributeKey: string;
-	/**
-	 * An attribute value offset, based on the rich
-	 * text value. See `wp.richText.create`.
-	 */
-	offset: number;
-};
-
 export type EqualityFieldCheck<
 	State extends BaseState,
 	FieldName extends keyof State,
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index 5d4b7bd08aabc5..c25f28b746245b 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -25,15 +25,13 @@ import type {
 	SyncConfig,
 	SyncManager,
 	SyncUndoManager,
+	AwarenessID,
 } from './types';
 import { createUndoManager } from './undo-manager';
 import { createYjsDoc } from './utils';
 import { createAwareness } from './awareness/awareness-manager';
 import type { AwarenessState } from './awareness/awareness-state';
 
-const AWARENESS_INSTANCE_SEPARATOR = ':';
-const ENTITY_INSTANCE_SEPARATOR = '_';
-
 interface EntityState {
 	handlers: RecordHandlers;
 	objectId: ObjectID;
@@ -50,7 +48,7 @@ interface EntityState {
  */
 export function createSyncManager(): SyncManager {
 	const entityStates: Map< EntityID, EntityState > = new Map();
-	const awarenessInstances: Map< string, AwarenessState > = new Map();
+	const awarenessInstances: Map< AwarenessID, AwarenessState > = new Map();
 
 	/**
 	 * A "sync-aware" undo manager for all synced entities. It is lazily created
@@ -230,7 +228,7 @@ export function createSyncManager(): SyncManager {
 		objectType: ObjectType,
 		objectId: ObjectID
 	): EntityID {
-		return getInstanceId( objectType, objectId, ENTITY_INSTANCE_SEPARATOR );
+		return `${ objectType }_${ objectId }`;
 	}
 
 	/**
@@ -242,27 +240,8 @@ export function createSyncManager(): SyncManager {
 	function getAwarenessId(
 		objectType: ObjectType,
 		objectId: ObjectID
-	): string {
-		return getInstanceId(
-			objectType,
-			objectId,
-			AWARENESS_INSTANCE_SEPARATOR
-		);
-	}
-
-	/**
-	 * Get the instance ID for the given object type and object ID.
-	 *
-	 * @param {ObjectType} objectType Object type.
-	 * @param {ObjectID}   objectId   Object ID.
-	 * @param {string}     separator  Separator between object type and object ID.
-	 */
-	function getInstanceId(
-		objectType: ObjectType,
-		objectId: ObjectID,
-		separator: string
-	): string {
-		return `${ objectType }${ separator }${ objectId }`;
+	): AwarenessID {
+		return `${ objectType }:${ objectId }`;
 	}
 
 	/**
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index b1cf0ce3660f01..6c3a15593cee60 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -31,6 +31,7 @@ declare global {
 }
 
 export type CRDTDoc = Y.Doc;
+export type AwarenessID = string;
 export type EntityID = string;
 export type ObjectID = string;
 export type ObjectType = string;

From 96c6e6a0d25b9264bc8dfc9093302fffab66d775 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 16:15:57 +1100
Subject: [PATCH 20/30] Added a todo for local storage

---
 packages/sync/src/local-storage.ts   |  2 ++
 packages/sync/src/selection-utils.ts | 14 --------------
 packages/sync/src/user-utils.ts      |  2 ++
 3 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/packages/sync/src/local-storage.ts b/packages/sync/src/local-storage.ts
index b249d1306183b1..b1465288020a90 100644
--- a/packages/sync/src/local-storage.ts
+++ b/packages/sync/src/local-storage.ts
@@ -1,3 +1,5 @@
+// TODO: Drop this file, and use @wordpress/preferences instead.
+
 /**
  * Load data from localStorage with error handling
  * @param key          - The localStorage key to read from
diff --git a/packages/sync/src/selection-utils.ts b/packages/sync/src/selection-utils.ts
index 520fc7b8335597..9ff8839cc9d012 100644
--- a/packages/sync/src/selection-utils.ts
+++ b/packages/sync/src/selection-utils.ts
@@ -8,20 +8,6 @@ import type * as Y from 'yjs';
  */
 import type { EditorState } from './awareness/awareness-types';
 
-/**
- * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
- */
-type BlockClientId = string;
-type BlockInnerBlocks = Y.Array< SelectableBlock >;
-type BlockAttributes = Y.Map< Y.Text >;
-
-/**
- * A block that can be selected.
- */
-export type SelectableBlock = Y.Map<
-	BlockClientId | BlockAttributes | BlockInnerBlocks
->;
-
 /**
  * The type of selection.
  */
diff --git a/packages/sync/src/user-utils.ts b/packages/sync/src/user-utils.ts
index 97543d08fbe48a..b84bb24c3c0b48 100644
--- a/packages/sync/src/user-utils.ts
+++ b/packages/sync/src/user-utils.ts
@@ -40,6 +40,7 @@ export function getNewUserColor( existingColors: string[] ): string {
 		( color ) => ! existingColors.includes( color )
 	);
 
+	// TODO: Drop this, and use @wordpress/preferences instead.
 	const preferredColor = loadFromLocalStorage< string | null >(
 		LOCAL_STORAGE_KEY,
 		null
@@ -59,6 +60,7 @@ export function getNewUserColor( existingColors: string[] ): string {
 		hexColor = generateColorVariation( baseColor );
 	}
 
+	// TODO: Drop this, and use @wordpress/preferences instead.
 	saveToLocalStorage( LOCAL_STORAGE_KEY, hexColor );
 	return hexColor;
 }

From 40bba56f9360c9251639f8559bad5e0741c7a275 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 16:23:09 +1100
Subject: [PATCH 21/30] Remove the block-editor fix

---
 packages/core-data/src/utils/test/crdt-blocks.ts | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/packages/core-data/src/utils/test/crdt-blocks.ts b/packages/core-data/src/utils/test/crdt-blocks.ts
index f03453c6582bac..9cf9a648e19370 100644
--- a/packages/core-data/src/utils/test/crdt-blocks.ts
+++ b/packages/core-data/src/utils/test/crdt-blocks.ts
@@ -34,13 +34,6 @@ jest.mock( '@wordpress/blocks', () => ( {
 	],
 } ) );
 
-/**
- * Mock @wordpress/block-editor to avoid private-apis unlock errors
- */
-jest.mock( '@wordpress/block-editor', () => ( {
-	store: {},
-} ) );
-
 /**
  * Internal dependencies
  */

From 9fb1542f6a2134de8808e021ee93d186b8698140 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Wed, 21 Jan 2026 21:10:08 +1100
Subject: [PATCH 22/30] Fix the test using STORE_NAME

---
 packages/core-data/src/test/resolvers.js             |  2 ++
 packages/core-data/src/utils/crdt-user-selections.ts | 12 +++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/packages/core-data/src/test/resolvers.js b/packages/core-data/src/test/resolvers.js
index f1e66c946bd7d2..9fef71adfba704 100644
--- a/packages/core-data/src/test/resolvers.js
+++ b/packages/core-data/src/test/resolvers.js
@@ -173,6 +173,7 @@ describe( 'getEntityRecord', () => {
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
 				getCurrentUser: expect.any( Function ),
+				subscribeToUserSelectionChanges: expect.any( Function ),
 			}
 		);
 	} );
@@ -227,6 +228,7 @@ describe( 'getEntityRecord', () => {
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
 				getCurrentUser: expect.any( Function ),
+				subscribeToUserSelectionChanges: expect.any( Function ),
 			}
 		);
 	} );
diff --git a/packages/core-data/src/utils/crdt-user-selections.ts b/packages/core-data/src/utils/crdt-user-selections.ts
index f2cad5437089e8..91e5a9ed5cc884 100644
--- a/packages/core-data/src/utils/crdt-user-selections.ts
+++ b/packages/core-data/src/utils/crdt-user-selections.ts
@@ -13,7 +13,7 @@ import { store as blockEditorStore } from '@wordpress/block-editor';
 /**
  * Internal dependencies
  */
-import { store as coreStore } from '../';
+import { STORE_NAME } from '../name';
 import { type WPBlockSelection } from '../types';
 
 /**
@@ -308,9 +308,15 @@ export async function updateSelectionInEntityRecord(
 	const options = {
 		undoIgnore: true,
 	};
-	const { editEntityRecord } = dispatch( coreStore );
 
-	editEntityRecord( kind, name, recordId, edits, options );
+	// @ts-ignore - Using STORE_NAME to avoid a circular dependency in the tests.
+	dispatch( STORE_NAME ).editEntityRecord(
+		kind,
+		name,
+		recordId,
+		edits,
+		options
+	);
 }
 
 /**

From 266fd2ca4487f51644788055feb7c6a54202f6ae Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Thu, 22 Jan 2026 15:37:25 +1100
Subject: [PATCH 23/30] Move awareness implementation details to core-data, and
 only leave the base interface behind

---
 packages/core-data/src/entities.js            |  25 ++
 .../core-data/src/post-editor-awareness.ts    | 157 +++++++++
 packages/core-data/src/resolvers.js           |  23 +-
 packages/core-data/src/test/resolvers.js      |   4 -
 packages/core-data/src/types.ts               | 106 ++++++
 .../src/utils/crdt-user-selections.ts         | 330 ++++++------------
 packages/sync/README.md                       |  46 +++
 .../sync/src/awareness/awareness-manager.ts   |  62 ----
 .../sync/src/awareness/awareness-state.ts     |   8 +-
 .../sync/src/awareness/awareness-types.ts     |  22 +-
 .../awareness/post-editor-awareness-state.ts  |  31 --
 packages/sync/src/index.ts                    |   4 +
 packages/sync/src/manager.ts                  |  60 ++--
 packages/sync/src/selection-utils.ts          | 193 ----------
 packages/sync/src/test/manager.ts             |  69 ++--
 packages/sync/src/types.ts                    |  19 +-
 packages/sync/src/user-utils.ts               |  32 +-
 17 files changed, 577 insertions(+), 614 deletions(-)
 create mode 100644 packages/core-data/src/post-editor-awareness.ts
 delete mode 100644 packages/sync/src/awareness/awareness-manager.ts
 delete mode 100644 packages/sync/src/awareness/post-editor-awareness-state.ts
 delete mode 100644 packages/sync/src/selection-utils.ts

diff --git a/packages/core-data/src/entities.js b/packages/core-data/src/entities.js
index eb8723698a60df..8bf1894b90801b 100644
--- a/packages/core-data/src/entities.js
+++ b/packages/core-data/src/entities.js
@@ -9,6 +9,7 @@ import { capitalCase, pascalCase } from 'change-case';
 import apiFetch from '@wordpress/api-fetch';
 import { __unstableSerializeAndClean, parse } from '@wordpress/blocks';
 import { __ } from '@wordpress/i18n';
+import { generateUserInfo } from '@wordpress/sync';
 
 /**
  * Internal dependencies
@@ -18,6 +19,7 @@ import {
 	applyPostChangesToCRDTDoc,
 	getPostChangesFromCRDTDoc,
 } from './utils/crdt';
+import { PostEditorAwareness } from './post-editor-awareness';
 
 export const DEFAULT_ENTITY_KEY = 'id';
 const POST_RAW_ATTRIBUTES = [ 'title', 'excerpt', 'content' ];
@@ -381,6 +383,29 @@ async function loadPostTypeEntities() {
 				supports: {
 					crdtPersistence: true,
 				},
+
+				createAwareness: ( ydoc, recordHandlers, currentUser ) => {
+					const awareness = new PostEditorAwareness( ydoc );
+
+					const states = awareness.getStates();
+					const otherUserColors = Array.from( states.entries() )
+						.filter(
+							( [ clientId, state ] ) =>
+								state.userInfo &&
+								clientId !== awareness.clientID
+						)
+						.map( ( [ , state ] ) => state.userInfo.color )
+						.filter( Boolean );
+
+					const userInfo = generateUserInfo(
+						currentUser,
+						otherUserColors
+					);
+
+					awareness.setUp( recordHandlers, userInfo );
+
+					return awareness;
+				},
 			};
 		}
 
diff --git a/packages/core-data/src/post-editor-awareness.ts b/packages/core-data/src/post-editor-awareness.ts
new file mode 100644
index 00000000000000..ac46c0fc1526c8
--- /dev/null
+++ b/packages/core-data/src/post-editor-awareness.ts
@@ -0,0 +1,157 @@
+/**
+ * WordPress dependencies
+ */
+import { select, subscribe } from '@wordpress/data';
+import {
+	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
+	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
+	type RecordHandlers,
+	AwarenessState,
+	type UserInfo,
+	areUserInfosEqual,
+} from '@wordpress/sync';
+// @ts-ignore No exported types for block editor store selectors.
+import { store as blockEditorStore } from '@wordpress/block-editor';
+
+/**
+ * Internal dependencies
+ */
+import {
+	areSelectionsStatesEqual,
+	getSelectionState,
+} from './utils/crdt-user-selections';
+import type { WPBlockSelection, PostEditorState, EditorState } from './types';
+
+export class PostEditorAwareness extends AwarenessState< PostEditorState > {
+	protected equalityFieldChecks = {
+		editorState: this.areEditorStatesEqual,
+		userInfo: areUserInfosEqual,
+	};
+
+	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
+		super.setUp( recordHandlers, userInfo );
+
+		this.subscribeToUserSelectionChanges( recordHandlers );
+	}
+
+	/**
+	 * Subscribe to user selection changes and update the selection state.
+	 *
+	 * @param recordHandlers - The record handlers.
+	 */
+	private subscribeToUserSelectionChanges(
+		recordHandlers: RecordHandlers
+	): void {
+		const {
+			getSelectionStart,
+			getSelectionEnd,
+			getSelectedBlocksInitialCaretPosition,
+		} = select( blockEditorStore );
+
+		// Keep track of the current selection in the outer scope so we can compare
+		// in the subscription.
+		let selectionStart = getSelectionStart();
+		let selectionEnd = getSelectionEnd();
+		let localCursorTimeout: NodeJS.Timeout | null = null;
+
+		subscribe( () => {
+			const newSelectionStart = getSelectionStart();
+			const newSelectionEnd = getSelectionEnd();
+
+			if (
+				newSelectionStart === selectionStart &&
+				newSelectionEnd === selectionEnd
+			) {
+				return;
+			}
+
+			selectionStart = newSelectionStart;
+			selectionEnd = newSelectionEnd;
+
+			// Typically selection position is only persisted after typing in a block, which
+			// can cause selection position to be reset by other users making block updates.
+			// Ensure we update the controlled selection right away, persisting our cursor position locally.
+			const initialPosition = getSelectedBlocksInitialCaretPosition();
+			void this.updateSelectionInEntityRecord(
+				recordHandlers,
+				selectionStart,
+				selectionEnd,
+				initialPosition
+			);
+
+			// We receive two selection changes in quick succession
+			// from local selection events:
+			//   { clientId: "123...", attributeKey: "content", offset: undefined }
+			//   { clientId: "123...", attributeKey: "content", offset: 554 }
+			// Add a short debounce to avoid sending the first selection change.
+			if ( localCursorTimeout ) {
+				clearTimeout( localCursorTimeout );
+			}
+
+			localCursorTimeout = setTimeout( () => {
+				const selectionState = getSelectionState(
+					selectionStart,
+					selectionEnd,
+					this.doc
+				);
+
+				this.setThrottledLocalStateField(
+					'editorState',
+					{ selection: selectionState },
+					AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
+				);
+			}, LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS );
+		} );
+	}
+
+	/**
+	 * Update the entity record with the current user's selection.
+	 *
+	 * @param recordHandlers
+	 * @param selectionStart  - The start position of the selection.
+	 * @param selectionEnd    - The end position of the selection.
+	 * @param initialPosition - The initial position of the selection.
+	 */
+	private async updateSelectionInEntityRecord(
+		recordHandlers: RecordHandlers,
+		selectionStart: WPBlockSelection,
+		selectionEnd: WPBlockSelection,
+		initialPosition: number | null
+	): Promise< void > {
+		// Send an entityRecord `selection` update if we have a selection.
+		//
+		// Normally WordPress updates the `selection` property of the post when changes are made to blocks.
+		// In a multi-user setup, block changes can occur from other users. When an entity is updated from another
+		// user's changes, useBlockSync() in Gutenberg will reset the user's selection to the last saved selection.
+		//
+		// Manually adding an edit for each movement ensures that other user's changes to the document will
+		// not cause the local user's selection to reset to the last local change location.
+		const edits = {
+			selection: { selectionStart, selectionEnd, initialPosition },
+		};
+
+		const options = {
+			undoIgnore: true,
+		};
+
+		recordHandlers.editRecord( edits, options );
+	}
+
+	/**
+	 * Check if two editor states are equal.
+	 *
+	 * @param state1 - The first editor state.
+	 * @param state2 - The second editor state.
+	 * @return True if the editor states are equal, false otherwise.
+	 */
+	private areEditorStatesEqual(
+		state1?: EditorState,
+		state2?: EditorState
+	): boolean {
+		if ( ! state1 || ! state2 ) {
+			return state1 === state2;
+		}
+
+		return areSelectionsStatesEqual( state1.selection, state2.selection );
+	}
+}
diff --git a/packages/core-data/src/resolvers.js b/packages/core-data/src/resolvers.js
index 0d68f5166e23a2..1197772713aa64 100644
--- a/packages/core-data/src/resolvers.js
+++ b/packages/core-data/src/resolvers.js
@@ -26,7 +26,6 @@ import {
 	isNumericID,
 } from './utils';
 import { fetchBlockPatterns } from './fetch';
-import { subscribeToUserSelectionChanges } from './utils/crdt-user-selections';
 
 /**
  * Requests authors from the REST API.
@@ -185,6 +184,8 @@ export const getEntityRecord =
 								transientConfig.read( recordWithTransients );
 						} );
 
+					const currentUser = await resolveSelect.getCurrentUser();
+
 					// Load the entity record for syncing.
 					await getSyncManager()?.load(
 						entityConfig.syncConfig,
@@ -234,24 +235,8 @@ export const getEntityRecord =
 									key
 								);
 							},
-							// Get the current user.
-							getCurrentUser: async () => {
-								await resolveSelect.getCurrentUser();
-							},
-							// Subscribe to user selection changes.
-							subscribeToUserSelectionChanges: (
-								yDoc,
-								setSelectionState
-							) => {
-								subscribeToUserSelectionChanges(
-									kind,
-									name,
-									key,
-									yDoc,
-									setSelectionState
-								);
-							},
-						}
+						},
+						currentUser
 					);
 				}
 			}
diff --git a/packages/core-data/src/test/resolvers.js b/packages/core-data/src/test/resolvers.js
index 9fef71adfba704..60e56079ee9a7c 100644
--- a/packages/core-data/src/test/resolvers.js
+++ b/packages/core-data/src/test/resolvers.js
@@ -172,8 +172,6 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-				getCurrentUser: expect.any( Function ),
-				subscribeToUserSelectionChanges: expect.any( Function ),
 			}
 		);
 	} );
@@ -227,8 +225,6 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-				getCurrentUser: expect.any( Function ),
-				subscribeToUserSelectionChanges: expect.any( Function ),
 			}
 		);
 	} );
diff --git a/packages/core-data/src/types.ts b/packages/core-data/src/types.ts
index dac976505a8f2d..df42fcee0e6a28 100644
--- a/packages/core-data/src/types.ts
+++ b/packages/core-data/src/types.ts
@@ -1,3 +1,8 @@
+/**
+ * External dependencies
+ */
+import type { Y, BaseState } from '@wordpress/sync';
+
 export interface AnyFunction {
 	( ...args: any[] ): any;
 }
@@ -13,3 +18,104 @@ export interface WPSelection {
 	selectionEnd: WPBlockSelection;
 	selectionStart: WPBlockSelection;
 }
+
+/**
+ * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
+ */
+export type BlockInnerBlocks = Y.Array< SelectableBlock >;
+type BlockClientId = string;
+type BlockAttributes = Y.Map< Y.Text >;
+
+/**
+ * A block that can be selected.
+ */
+export type SelectableBlock = Y.Map<
+	BlockClientId | BlockAttributes | BlockInnerBlocks
+>;
+
+/**
+ * The type of selection.
+ */
+export enum SelectionType {
+	None = 'none',
+	Cursor = 'cursor',
+	SelectionInOneBlock = 'selection-in-one-block',
+	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
+	WholeBlock = 'whole-block',
+}
+
+/**
+ * The position of the cursor.
+ */
+export type CursorPosition = {
+	relativePosition: Y.RelativePosition;
+
+	// Also store the absolute offset index of the cursor from the perspective
+	// of the user who is updating the selection.
+	//
+	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
+	// on relativePosition for the most up-to-date positioning.
+	//
+	// This is used because local Y.Text changes (e.g. adding or deleting a character)
+	// can result in the same relative position if it is pinned to an unchanged
+	// character. With both of these values as editor state, a change in perceived
+	// position will always result in a redraw.
+	absoluteOffset: number;
+};
+
+export type SelectionNone = {
+	// The user has not made a selection.
+	type: SelectionType.None;
+};
+
+export type SelectionCursor = {
+	// The user has a cursor position in a block with no text highlighted.
+	type: SelectionType.Cursor;
+	blockId: string;
+	cursorPosition: CursorPosition;
+};
+
+export type SelectionInOneBlock = {
+	// The user has highlighted text in a single block.
+	type: SelectionType.SelectionInOneBlock;
+	blockId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionInMultipleBlocks = {
+	// The user has highlighted text over multiple blocks.
+	type: SelectionType.SelectionInMultipleBlocks;
+	blockStartId: string;
+	blockEndId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionWholeBlock = {
+	// The user has a non-text block selected, like an image block.
+	type: SelectionType.WholeBlock;
+	blockId: string;
+};
+
+export type SelectionState =
+	| SelectionNone
+	| SelectionCursor
+	| SelectionInOneBlock
+	| SelectionInMultipleBlocks
+	| SelectionWholeBlock;
+
+/**
+ * The editor state includes information about the user's current selection.
+ */
+export interface EditorState {
+	selection: SelectionState;
+}
+
+/**
+ * The post editor state extends the base state with information used to render
+ * presence indicators in the post editor.
+ */
+export interface PostEditorState extends BaseState {
+	editorState?: EditorState;
+}
diff --git a/packages/core-data/src/utils/crdt-user-selections.ts b/packages/core-data/src/utils/crdt-user-selections.ts
index 91e5a9ed5cc884..45ca50dc1706d2 100644
--- a/packages/core-data/src/utils/crdt-user-selections.ts
+++ b/packages/core-data/src/utils/crdt-user-selections.ts
@@ -1,181 +1,23 @@
 /**
- * WordPress dependencies
+ * External dependencies
  */
-import { dispatch, select, subscribe } from '@wordpress/data';
-import {
-	Y,
-	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
-	CRDT_RECORD_MAP_KEY,
-} from '@wordpress/sync';
-// @ts-ignore No exported types for block editor store selectors.
-import { store as blockEditorStore } from '@wordpress/block-editor';
+import { Y, CRDT_RECORD_MAP_KEY } from '@wordpress/sync';
 
 /**
  * Internal dependencies
  */
-import { STORE_NAME } from '../name';
-import { type WPBlockSelection } from '../types';
-
-/**
- * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
- */
-type BlockClientId = string;
-type BlockInnerBlocks = Y.Array< SelectableBlock >;
-type BlockAttributes = Y.Map< Y.Text >;
-
-/**
- * A block that can be selected.
- */
-export type SelectableBlock = Y.Map<
-	BlockClientId | BlockAttributes | BlockInnerBlocks
->;
-
-/**
- * The type of selection.
- */
-export enum SelectionType {
-	None = 'none',
-	Cursor = 'cursor',
-	SelectionInOneBlock = 'selection-in-one-block',
-	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
-	WholeBlock = 'whole-block',
-}
-
-/**
- * The position of the cursor.
- */
-export type CursorPosition = {
-	relativePosition: Y.RelativePosition;
-
-	// Also store the absolute offset index of the cursor from the perspective
-	// of the user who is updating the selection.
-	//
-	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
-	// on relativePosition for the most up-to-date positioning.
-	//
-	// This is used because local Y.Text changes (e.g. adding or deleting a character)
-	// can result in the same relative position if it is pinned to an unchanged
-	// character. With both of these values as editor state, a change in perceived
-	// position will always result in a redraw.
-	absoluteOffset: number;
-};
-
-export type SelectionNone = {
-	// The user has not made a selection.
-	type: SelectionType.None;
-};
-
-export type SelectionCursor = {
-	// The user has a cursor position in a block with no text highlighted.
-	type: SelectionType.Cursor;
-	blockId: string;
-	cursorPosition: CursorPosition;
-};
-
-export type SelectionInOneBlock = {
-	// The user has highlighted text in a single block.
-	type: SelectionType.SelectionInOneBlock;
-	blockId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionInMultipleBlocks = {
-	// The user has highlighted text over multiple blocks.
-	type: SelectionType.SelectionInMultipleBlocks;
-	blockStartId: string;
-	blockEndId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionWholeBlock = {
-	// The user has a non-text block selected, like an image block.
-	type: SelectionType.WholeBlock;
-	blockId: string;
-};
-
-export type SelectionState =
-	| SelectionNone
-	| SelectionCursor
-	| SelectionInOneBlock
-	| SelectionInMultipleBlocks
-	| SelectionWholeBlock;
-
-/**
- * Subscribe to user selection changes and update the selection state.
- *
- * @param kind              - The kind of entity.
- * @param name              - The name of the entity.
- * @param recordId          - The ID of the entity.
- * @param yDoc              - Y.Doc
- * @param setSelectionState - The function to set the selection state.
- */
-export function subscribeToUserSelectionChanges(
-	kind: string,
-	name: string,
-	recordId: string | number,
-	yDoc: Y.Doc,
-	setSelectionState: ( selectionState: SelectionState ) => void
-): void {
-	const {
-		getSelectionStart,
-		getSelectionEnd,
-		getSelectedBlocksInitialCaretPosition,
-	} = select( blockEditorStore );
-
-	// Keep track of the current selection in the outer scope so we can compare
-	// in the subscription.
-	let selectionStart = getSelectionStart();
-	let selectionEnd = getSelectionEnd();
-	let localCursorTimeout: NodeJS.Timeout | null = null;
-
-	subscribe( () => {
-		const newSelectionStart = getSelectionStart();
-		const newSelectionEnd = getSelectionEnd();
-
-		if (
-			newSelectionStart === selectionStart &&
-			newSelectionEnd === selectionEnd
-		) {
-			return;
-		}
-
-		selectionStart = newSelectionStart;
-		selectionEnd = newSelectionEnd;
-
-		// Typically selection position is only persisted after typing in a block, which
-		// can cause selection position to be reset by other users making block updates.
-		// Ensure we update the controlled selection right away, persisting our cursor position locally.
-		const initialPosition = getSelectedBlocksInitialCaretPosition();
-		void updateSelectionInEntityRecord(
-			kind,
-			name,
-			recordId,
-			selectionStart,
-			selectionEnd,
-			initialPosition
-		);
-
-		// We receive two selection changes in quick succession
-		// from local selection events:
-		//   { clientId: "123...", attributeKey: "content", offset: undefined }
-		//   { clientId: "123...", attributeKey: "content", offset: 554 }
-		// Add a short debounce to avoid sending the first selection change.
-		if ( localCursorTimeout ) {
-			clearTimeout( localCursorTimeout );
-		}
-
-		localCursorTimeout = setTimeout( () => {
-			const selectionState = getSelectionState(
-				selectionStart,
-				selectionEnd,
-				yDoc
-			);
-			setSelectionState( selectionState );
-		}, LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS );
-	} );
-}
+import type {
+	WPBlockSelection,
+	SelectionState,
+	SelectableBlock,
+	CursorPosition,
+	SelectionNone,
+	SelectionCursor,
+	SelectionInOneBlock,
+	SelectionInMultipleBlocks,
+	SelectionWholeBlock,
+} from '../types';
+import { SelectionType, type BlockInnerBlocks } from '../types';
 
 /**
  * Converts WordPress block editor selection to a SelectionState.
@@ -185,7 +27,7 @@ export function subscribeToUserSelectionChanges(
  * @param yDoc           - The Yjs document
  * @return The SelectionState
  */
-function getSelectionState(
+export function getSelectionState(
 	selectionStart: WPBlockSelection,
 	selectionEnd: WPBlockSelection,
 	yDoc: Y.Doc
@@ -271,54 +113,6 @@ function getSelectionState(
 	};
 }
 
-/**
- * Update the entity record with the current user's selection.
- *
- * @param kind            - The kind of entity.
- * @param name            - The name of the entity.
- * @param recordId        - The ID of the entity.
- * @param selectionStart  - The start position of the selection.
- * @param selectionEnd    - The end position of the selection.
- * @param initialPosition - The initial position of the selection.
- */
-export async function updateSelectionInEntityRecord(
-	kind: string,
-	name: string,
-	recordId: string | number,
-	selectionStart: WPBlockSelection,
-	selectionEnd: WPBlockSelection,
-	initialPosition: number | null
-): Promise< void > {
-	if ( ! selectionStart.clientId ) {
-		return;
-	}
-
-	// Send an entityRecord `selection` update if we have a selection.
-	//
-	// Normally WordPress updates the `selection` property of the post when changes are made to blocks.
-	// In a multi-user setup, block changes can occur from other users. When an entity is updated from another
-	// user's changes, useBlockSync() in Gutenberg will reset the user's selection to the last saved selection.
-	//
-	// Manually adding an edit for each movement ensures that other user's changes to the document will
-	// not cause the local user's selection to reset to the last local change location.
-	const edits = {
-		selection: { selectionStart, selectionEnd, initialPosition },
-	};
-
-	const options = {
-		undoIgnore: true,
-	};
-
-	// @ts-ignore - Using STORE_NAME to avoid a circular dependency in the tests.
-	dispatch( STORE_NAME ).editEntityRecord(
-		kind,
-		name,
-		recordId,
-		edits,
-		options
-	);
-}
-
 /**
  * Get the cursor position from a selection.
  *
@@ -381,3 +175,97 @@ function findBlockByClientId(
 
 	return null;
 }
+
+/**
+ * Check if two selection states are equal.
+ *
+ * @param selection1 - The first selection state.
+ * @param selection2 - The second selection state.
+ * @return True if the selection states are equal, false otherwise.
+ */
+export function areSelectionsStatesEqual(
+	selection1: SelectionState,
+	selection2: SelectionState
+): boolean {
+	if ( selection1.type !== selection2.type ) {
+		return false;
+	}
+
+	switch ( selection1.type ) {
+		case SelectionType.None:
+			return true;
+
+		case SelectionType.Cursor:
+			return (
+				selection1.blockId ===
+					( selection2 as SelectionCursor ).blockId &&
+				areCursorPositionsEqual(
+					selection1.cursorPosition,
+					( selection2 as SelectionCursor ).cursorPosition
+				)
+			);
+
+		case SelectionType.SelectionInOneBlock:
+			return (
+				selection1.blockId ===
+					( selection2 as SelectionInOneBlock ).blockId &&
+				areCursorPositionsEqual(
+					selection1.cursorStartPosition,
+					( selection2 as SelectionInOneBlock ).cursorStartPosition
+				) &&
+				areCursorPositionsEqual(
+					selection1.cursorEndPosition,
+					( selection2 as SelectionInOneBlock ).cursorEndPosition
+				)
+			);
+
+		case SelectionType.SelectionInMultipleBlocks:
+			return (
+				selection1.blockStartId ===
+					( selection2 as SelectionInMultipleBlocks ).blockStartId &&
+				selection1.blockEndId ===
+					( selection2 as SelectionInMultipleBlocks ).blockEndId &&
+				areCursorPositionsEqual(
+					selection1.cursorStartPosition,
+					( selection2 as SelectionInMultipleBlocks )
+						.cursorStartPosition
+				) &&
+				areCursorPositionsEqual(
+					selection1.cursorEndPosition,
+					( selection2 as SelectionInMultipleBlocks )
+						.cursorEndPosition
+				)
+			);
+		case SelectionType.WholeBlock:
+			return (
+				selection1.blockId ===
+				( selection2 as SelectionWholeBlock ).blockId
+			);
+
+		default:
+			return false;
+	}
+}
+
+/**
+ * Check if two cursor positions are equal.
+ *
+ * @param cursorPosition1 - The first cursor position.
+ * @param cursorPosition2 - The second cursor position.
+ * @return True if the cursor positions are equal, false otherwise.
+ */
+function areCursorPositionsEqual(
+	cursorPosition1: CursorPosition,
+	cursorPosition2: CursorPosition
+): boolean {
+	const isRelativePositionEqual =
+		JSON.stringify( cursorPosition1.relativePosition ) ===
+		JSON.stringify( cursorPosition2.relativePosition );
+
+	// Ensure a change in calculated absolute offset results in a treating the cursor as modified.
+	// This is necessary because Y.Text relative positions can remain the same after text changes.
+	const isAbsoluteOffsetEqual =
+		cursorPosition1.absoluteOffset === cursorPosition2.absoluteOffset;
+
+	return isRelativePositionEqual && isAbsoluteOffsetEqual;
+}
diff --git a/packages/sync/README.md b/packages/sync/README.md
index 4041ab010d5772..5b29008f7a8bf3 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -14,6 +14,31 @@ npm install @wordpress/sync --save
 
 <!-- START TOKEN(Autogenerated API docs) -->
 
+### areUserInfosEqual
+
+Check if two user infos are equal.
+
+_Parameters_
+
+-   _userInfo1_ `UserInfo`: - The first user info.
+-   _userInfo2_ `UserInfo`: - The second user info.
+
+_Returns_
+
+-   `boolean`: True if the user infos are equal, false otherwise.
+
+### AwarenessState
+
+Abstract class to manage awareness and allow external code to subscribe to state updates.
+
+_Type_
+
+-   `AwarenessState`
+
+### AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
+
+Delay in milliseconds before throttling the cursor position updates.
+
 ### CRDT_DOC_META_PERSISTENCE_KEY
 
 CRDT documents can hold meta information in a map. This map exists only in memory and is not synced or persisted. This key can be used to indicate that a (temporary) document has been loaded from persistence.
@@ -42,6 +67,19 @@ The sync manager orchestrates the lifecycle of syncing entity records. It create
 
 Deltas are used to calculate incremental Y.Text updates.
 
+### generateUserInfo
+
+Generate a user info object from a current user and a list of existing colors.
+
+_Parameters_
+
+-   _currentUser_ `WordPressUserInfo`: - The current user.
+-   _existingColors_ `string[]`: - The existing colors.
+
+_Returns_
+
+-   `UserInfo`: The user info object.
+
 ### LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS
 
 Delay in milliseconds before updating the cursor position.
@@ -54,6 +92,14 @@ Origin string for CRDT document changes originating from the local editor.
 
 Origin string for CRDT document changes originating from the sync manager.
 
+### TypedAwareness
+
+Extended Awareness class with typed state accessors.
+
+_Type_
+
+-   `TypedAwareness`
+
 ### WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE
 
 WordPress meta key used to persist the CRDT document for an entity.
diff --git a/packages/sync/src/awareness/awareness-manager.ts b/packages/sync/src/awareness/awareness-manager.ts
deleted file mode 100644
index 625b61b6d64195..00000000000000
--- a/packages/sync/src/awareness/awareness-manager.ts
+++ /dev/null
@@ -1,62 +0,0 @@
-/**
- * External dependencies
- */
-import type * as Y from 'yjs';
-
-/**
- * Internal dependencies
- */
-import type { ObjectID, ObjectType, RecordHandlers } from '../types';
-import type { AwarenessState } from './awareness-state';
-import { PostEditorAwarenessState } from './post-editor-awareness-state';
-import type { UserInfo, WordPressUserInfo } from './awareness-types';
-import { getBrowserName, getNewUserColor } from '../user-utils';
-
-function getUserInfo(
-	awareness: AwarenessState,
-	wpUser: WordPressUserInfo
-): UserInfo {
-	const states = awareness.getStates();
-	// TODO: There is a timing issue here. The other users aren't yet synced, and as a result the same color could be assigned to multiple users.
-	const otherUserColors = Array.from( states.entries() )
-		.filter(
-			( [ clientId, state ] ) =>
-				state.userInfo && clientId !== awareness.clientID
-		)
-		.map( ( [ , state ] ) => state.userInfo.color )
-		.filter( Boolean );
-
-	return {
-		...wpUser,
-		browserType: getBrowserName(),
-		color: getNewUserColor( otherUserColors ),
-		enteredAt: Date.now(),
-	};
-}
-
-/**
- * Create an awareness instance for the given object type and object ID.
- * @param objectType     Object type.
- * @param objectId       Object ID.
- * @param ydoc           Yjs document.
- * @param recordHandlers Record handlers.
- * @return Awareness instance.
- */
-export async function createAwareness(
-	objectType: ObjectType,
-	objectId: ObjectID | null,
-	ydoc: Y.Doc,
-	recordHandlers: RecordHandlers
-): Promise< AwarenessState | undefined > {
-	if ( objectId && objectType.startsWith( 'postType/' ) ) {
-		const awareness = new PostEditorAwarenessState( ydoc );
-
-		const currentUser = await recordHandlers.getCurrentUser();
-		const userInfo = getUserInfo( awareness, currentUser );
-
-		awareness.setUp( recordHandlers, userInfo );
-
-		return awareness;
-	}
-	return undefined;
-}
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 923a2aabf3947d..3506513e924b30 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -2,6 +2,7 @@
  * Internal dependencies
  */
 import type { UserInfo } from './awareness-types';
+import type { RecordHandlers } from '../types';
 import {
 	TypedAwareness,
 	type BaseState,
@@ -10,7 +11,6 @@ import {
 } from './awareness-types';
 import { getTypedKeys, areMapsEqual } from '../utils';
 import { REMOVAL_DELAY_IN_MS } from '../config';
-import type { RecordHandlers } from '../types';
 
 type AwarenessClientID = number;
 
@@ -152,10 +152,10 @@ export abstract class AwarenessState<
 
 	/**
 	 * Set up the awareness state.
-	 * @param _recordHandlers - Record handlers.
-	 * @param userInfo        - User info.
+	 * @param recordHandlers - Record handlers.
+	 * @param userInfo       - User info.
 	 */
-	public setUp( _recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
+	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
 		this.setLocalStateField( 'userInfo', userInfo );
 
 		this.on(
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index 3ed2ea929d9500..fa92cf2a80453d 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -1,7 +1,12 @@
+/**
+ * External dependencies
+ */
 import { Awareness } from 'y-protocols/awareness';
 
+/**
+ * Internal dependencies
+ */
 import { getRecordValue } from '../utils';
-import type { SelectionState } from '../selection-utils';
 
 /**
  * Extended Awareness class with typed state accessors.
@@ -86,18 +91,3 @@ export type EqualityFieldCheck<
 	State extends BaseState,
 	FieldName extends keyof State,
 > = ( value1?: State[ FieldName ], value2?: State[ FieldName ] ) => boolean;
-
-/**
- * The editor state includes information about the user's current selection.
- */
-export interface EditorState {
-	selection: SelectionState;
-}
-
-/**
- * The post editor state extends the base state with information used to render
- * presence indicators in the post editor.
- */
-export interface PostEditorState extends BaseState {
-	editorState?: EditorState;
-}
diff --git a/packages/sync/src/awareness/post-editor-awareness-state.ts b/packages/sync/src/awareness/post-editor-awareness-state.ts
deleted file mode 100644
index 8e6e551d0ebbd1..00000000000000
--- a/packages/sync/src/awareness/post-editor-awareness-state.ts
+++ /dev/null
@@ -1,31 +0,0 @@
-/**
- * Internal dependencies
- */
-import type { PostEditorState, UserInfo } from './awareness-types';
-import type { RecordHandlers } from '../types';
-import { AwarenessState } from './awareness-state';
-import { areUserInfosEqual } from '../user-utils';
-import { AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS } from '../config';
-import { areEditorStatesEqual } from '../selection-utils';
-
-export class PostEditorAwarenessState extends AwarenessState< PostEditorState > {
-	protected equalityFieldChecks = {
-		editorState: areEditorStatesEqual,
-		userInfo: areUserInfosEqual,
-	};
-
-	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
-		super.setUp( recordHandlers, userInfo );
-
-		// Subscribe to user selection changes.
-		recordHandlers.subscribeToUserSelectionChanges(
-			this.doc,
-			( selectionState ) =>
-				this.setThrottledLocalStateField(
-					'editorState',
-					{ selection: selectionState },
-					AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
-				)
-		);
-	}
-}
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 6180aaa8e754e3..7bc9eea7b5e929 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -26,6 +26,10 @@ export {
 	LOCAL_SYNC_MANAGER_ORIGIN,
 	WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE,
 	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
+	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
 } from './config';
 export { createSyncManager } from './manager';
 export type * from './types';
+export type * from './awareness/awareness-types';
+export { AwarenessState } from './awareness/awareness-state';
+export { areUserInfosEqual, generateUserInfo } from './user-utils';
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index c25f28b746245b..ef999b44d17fe8 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -25,18 +25,18 @@ import type {
 	SyncConfig,
 	SyncManager,
 	SyncUndoManager,
-	AwarenessID,
 } from './types';
 import { createUndoManager } from './undo-manager';
 import { createYjsDoc } from './utils';
-import { createAwareness } from './awareness/awareness-manager';
 import type { AwarenessState } from './awareness/awareness-state';
+import type { WordPressUserInfo } from './awareness/awareness-types';
 
 interface EntityState {
 	handlers: RecordHandlers;
 	objectId: ObjectID;
 	objectType: ObjectType;
 	syncConfig: SyncConfig;
+	awareness?: AwarenessState;
 	unload: () => void;
 	ydoc: CRDTDoc;
 }
@@ -48,7 +48,6 @@ interface EntityState {
  */
 export function createSyncManager(): SyncManager {
 	const entityStates: Map< EntityID, EntityState > = new Map();
-	const awarenessInstances: Map< AwarenessID, AwarenessState > = new Map();
 
 	/**
 	 * A "sync-aware" undo manager for all synced entities. It is lazily created
@@ -84,18 +83,20 @@ export function createSyncManager(): SyncManager {
 	/**
 	 * Load an entity for syncing and manage its lifecycle.
 	 *
-	 * @param {SyncConfig}     syncConfig Sync configuration for the object type.
-	 * @param {ObjectType}     objectType Object type.
-	 * @param {ObjectID}       objectId   Object ID.
-	 * @param {ObjectData}     record     Entity record representing this object type.
-	 * @param {RecordHandlers} handlers   Handlers for updating and fetching the record.
+	 * @param {SyncConfig}        syncConfig  Sync configuration for the object type.
+	 * @param {ObjectType}        objectType  Object type.
+	 * @param {ObjectID}          objectId    Object ID.
+	 * @param {ObjectData}        record      Entity record representing this object type.
+	 * @param {RecordHandlers}    handlers    Handlers for updating and fetching the record.
+	 * @param {WordPressUserInfo} currentUser Current user.
 	 */
 	async function loadEntity(
 		syncConfig: SyncConfig,
 		objectType: ObjectType,
 		objectId: ObjectID,
 		record: ObjectData,
-		handlers: RecordHandlers
+		handlers: RecordHandlers,
+		currentUser: WordPressUserInfo
 	): Promise< void > {
 		const providerCreators = getProviderCreators();
 
@@ -109,8 +110,6 @@ export function createSyncManager(): SyncManager {
 			return; // Already bootstrapped.
 		}
 
-		const awarenessId = getAwarenessId( objectType, objectId );
-
 		const ydoc = createYjsDoc( { objectType } );
 		const recordMap = ydoc.getMap( RECORD_KEY );
 		const recordMetaMap = ydoc.getMap( RECORD_METADATA_KEY );
@@ -122,9 +121,15 @@ export function createSyncManager(): SyncManager {
 			recordMap.unobserveDeep( onRecordUpdate );
 			ydoc.destroy();
 			entityStates.delete( entityId );
-			awarenessInstances.delete( awarenessId );
 		};
 
+		// If the sync config supports awareness, create it.
+		const awareness = syncConfig.createAwareness?.(
+			ydoc,
+			handlers,
+			currentUser
+		);
+
 		// When the CRDT document is updated by an UndoManager or a connection (not
 		// a local origin), update the local store.
 		const onRecordUpdate = (
@@ -174,25 +179,13 @@ export function createSyncManager(): SyncManager {
 			objectId,
 			objectType,
 			syncConfig,
+			awareness,
 			unload,
 			ydoc,
 		};
 
 		entityStates.set( entityId, entityState );
 
-		// Create awareness for the given entity and its Yjs document.
-		const awareness = await createAwareness(
-			objectType,
-			objectId,
-			ydoc,
-			handlers
-		);
-
-		// Awareness can be undefined, if the object type is not supported.
-		if ( awareness ) {
-			awarenessInstances.set( awarenessId, awareness );
-		}
-
 		// Create providers for the given entity and its Yjs document.
 		const providerResults = await Promise.all(
 			providerCreators.map( ( create ) =>
@@ -232,16 +225,24 @@ export function createSyncManager(): SyncManager {
 	}
 
 	/**
-	 * Get the awareness ID for the given object type and object ID.
+	 * Get the awareness instance for the given object type and object ID, if supported.
 	 *
 	 * @param {ObjectType} objectType Object type.
 	 * @param {ObjectID}   objectId   Object ID.
+	 * @return {AwarenessState | undefined} The awareness instance, or undefined if not supported.
 	 */
-	function getAwarenessId(
+	function getAwarenessInstance(
 		objectType: ObjectType,
 		objectId: ObjectID
-	): AwarenessID {
-		return `${ objectType }:${ objectId }`;
+	): AwarenessState | undefined {
+		const entityId = getEntityId( objectType, objectId );
+		const entityState = entityStates.get( entityId );
+
+		if ( ! entityState || ! entityState.awareness ) {
+			return undefined;
+		}
+
+		return entityState.awareness;
 	}
 
 	/**
@@ -445,6 +446,7 @@ export function createSyncManager(): SyncManager {
 
 	return {
 		createMeta: createEntityMeta,
+		getAwarenessInstance,
 		load: loadEntity,
 		// Use getter to ensure we always return the current value of `undoManager`.
 		get undoManager(): SyncUndoManager | undefined {
diff --git a/packages/sync/src/selection-utils.ts b/packages/sync/src/selection-utils.ts
deleted file mode 100644
index 9ff8839cc9d012..00000000000000
--- a/packages/sync/src/selection-utils.ts
+++ /dev/null
@@ -1,193 +0,0 @@
-/**
- * External dependencies
- */
-import type * as Y from 'yjs';
-
-/**
- * Internal dependencies
- */
-import type { EditorState } from './awareness/awareness-types';
-
-/**
- * The type of selection.
- */
-export enum SelectionType {
-	None = 'none',
-	Cursor = 'cursor',
-	SelectionInOneBlock = 'selection-in-one-block',
-	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
-	WholeBlock = 'whole-block',
-}
-
-/**
- * The position of the cursor.
- */
-export type CursorPosition = {
-	relativePosition: Y.RelativePosition;
-
-	// Also store the absolute offset index of the cursor from the perspective
-	// of the user who is updating the selection.
-	//
-	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
-	// on relativePosition for the most up-to-date positioning.
-	//
-	// This is used because local Y.Text changes (e.g. adding or deleting a character)
-	// can result in the same relative position if it is pinned to an unchanged
-	// character. With both of these values as editor state, a change in perceived
-	// position will always result in a redraw.
-	absoluteOffset: number;
-};
-
-export type SelectionNone = {
-	// The user has not made a selection.
-	type: SelectionType.None;
-};
-
-export type SelectionCursor = {
-	// The user has a cursor position in a block with no text highlighted.
-	type: SelectionType.Cursor;
-	blockId: string;
-	cursorPosition: CursorPosition;
-};
-
-export type SelectionInOneBlock = {
-	// The user has highlighted text in a single block.
-	type: SelectionType.SelectionInOneBlock;
-	blockId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionInMultipleBlocks = {
-	// The user has highlighted text over multiple blocks.
-	type: SelectionType.SelectionInMultipleBlocks;
-	blockStartId: string;
-	blockEndId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionWholeBlock = {
-	// The user has a non-text block selected, like an image block.
-	type: SelectionType.WholeBlock;
-	blockId: string;
-};
-
-export type SelectionState =
-	| SelectionNone
-	| SelectionCursor
-	| SelectionInOneBlock
-	| SelectionInMultipleBlocks
-	| SelectionWholeBlock;
-
-/**
- * Check if two selection states are equal.
- *
- * @param selection1 - The first selection state.
- * @param selection2 - The second selection state.
- * @return True if the selection states are equal, false otherwise.
- */
-function areSelectionsEqual(
-	selection1: SelectionState,
-	selection2: SelectionState
-): boolean {
-	if ( selection1.type !== selection2.type ) {
-		return false;
-	}
-
-	switch ( selection1.type ) {
-		case SelectionType.None:
-			return true;
-
-		case SelectionType.Cursor:
-			return (
-				selection1.blockId ===
-					( selection2 as SelectionCursor ).blockId &&
-				areCursorPositionsEqual(
-					selection1.cursorPosition,
-					( selection2 as SelectionCursor ).cursorPosition
-				)
-			);
-
-		case SelectionType.SelectionInOneBlock:
-			return (
-				selection1.blockId ===
-					( selection2 as SelectionInOneBlock ).blockId &&
-				areCursorPositionsEqual(
-					selection1.cursorStartPosition,
-					( selection2 as SelectionInOneBlock ).cursorStartPosition
-				) &&
-				areCursorPositionsEqual(
-					selection1.cursorEndPosition,
-					( selection2 as SelectionInOneBlock ).cursorEndPosition
-				)
-			);
-
-		case SelectionType.SelectionInMultipleBlocks:
-			return (
-				selection1.blockStartId ===
-					( selection2 as SelectionInMultipleBlocks ).blockStartId &&
-				selection1.blockEndId ===
-					( selection2 as SelectionInMultipleBlocks ).blockEndId &&
-				areCursorPositionsEqual(
-					selection1.cursorStartPosition,
-					( selection2 as SelectionInMultipleBlocks )
-						.cursorStartPosition
-				) &&
-				areCursorPositionsEqual(
-					selection1.cursorEndPosition,
-					( selection2 as SelectionInMultipleBlocks )
-						.cursorEndPosition
-				)
-			);
-		case SelectionType.WholeBlock:
-			return (
-				selection1.blockId ===
-				( selection2 as SelectionWholeBlock ).blockId
-			);
-
-		default:
-			return false;
-	}
-}
-
-/**
- * Check if two editor states are equal.
- *
- * @param state1 - The first editor state.
- * @param state2 - The second editor state.
- * @return True if the editor states are equal, false otherwise.
- */
-export function areEditorStatesEqual(
-	state1?: EditorState,
-	state2?: EditorState
-): boolean {
-	if ( ! state1 || ! state2 ) {
-		return state1 === state2;
-	}
-
-	return areSelectionsEqual( state1.selection, state2.selection );
-}
-
-/**
- * Check if two cursor positions are equal.
- *
- * @param cursorPosition1 - The first cursor position.
- * @param cursorPosition2 - The second cursor position.
- * @return True if the cursor positions are equal, false otherwise.
- */
-function areCursorPositionsEqual(
-	cursorPosition1: CursorPosition,
-	cursorPosition2: CursorPosition
-): boolean {
-	const isRelativePositionEqual =
-		JSON.stringify( cursorPosition1.relativePosition ) ===
-		JSON.stringify( cursorPosition2.relativePosition );
-
-	// Ensure a change in calculated absolute offset results in a treating the cursor as modified.
-	// This is necessary because Y.Text relative positions can remain the same after text changes.
-	const isAbsoluteOffsetEqual =
-		cursorPosition1.absoluteOffset === cursorPosition2.absoluteOffset;
-
-	return isRelativePositionEqual && isAbsoluteOffsetEqual;
-}
diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index a16b64ecc06234..c214654697129c 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -96,6 +96,8 @@ describe( 'SyncManager', () => {
 				}
 			),
 			supports: {},
+			// TODO: Switch this to the generic awareness state implementation instead.
+			createAwareness: jest.fn( () => undefined ),
 		};
 
 		mockHandlers = {
@@ -105,10 +107,6 @@ describe( 'SyncManager', () => {
 			),
 			refetchRecord: jest.fn( async () => Promise.resolve() ),
 			saveRecord: jest.fn( async () => Promise.resolve() ),
-			getCurrentUser: jest.fn( async () =>
-				Promise.resolve( mockCurrentUser )
-			),
-			subscribeToUserSelectionChanges: jest.fn(),
 		};
 	} );
 
@@ -132,7 +130,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			// Verify that applyChangesToCRDTDoc was called with the record data
@@ -150,7 +149,8 @@ describe( 'SyncManager', () => {
 				'postType/post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			expect( mockProviderCreator ).toHaveBeenCalledTimes( 1 );
@@ -172,7 +172,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			expect(
@@ -189,7 +190,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			await manager.load(
@@ -197,7 +199,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			// Should only be called once despite two load attempts
@@ -218,7 +221,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				record1,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			await manager.load(
@@ -226,7 +230,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'456',
 				record2,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			expect(
@@ -274,7 +279,8 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					mockRecord,
-					mockHandlers
+					mockHandlers,
+					mockCurrentUser
 				);
 
 				// Current record should be applied as changes since the persisted doc does not exist.
@@ -309,7 +315,8 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers
+					mockHandlers,
+					mockCurrentUser
 				);
 
 				// Changes should NOT be applied since the persisted doc is valid.
@@ -348,7 +355,8 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers
+					mockHandlers,
+					mockCurrentUser
 				);
 
 				// Changes should be applied for the invalidated properties.
@@ -388,7 +396,8 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers
+					mockHandlers,
+					mockCurrentUser
 				);
 
 				// Current record should be applied since the persisted doc does not exist.
@@ -419,7 +428,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			manager.unload( 'post', '123' );
@@ -443,7 +453,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			manager.unload( 'post', '123' );
@@ -455,7 +466,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			expect(
@@ -472,7 +484,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			await manager.load(
@@ -480,7 +493,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'456',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			manager.unload( 'post', '123' );
@@ -518,7 +532,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			jest.clearAllMocks();
@@ -571,7 +586,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			// Get the captured Y.Doc
@@ -615,7 +631,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			jest.clearAllMocks();
@@ -663,7 +680,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			// Clear calls of editRecord, which is called during load.
@@ -712,7 +730,8 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers
+				mockHandlers,
+				mockCurrentUser
 			);
 
 			// Clear calls of editRecord, which is called during load.
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index 6c3a15593cee60..aaa8be713f2c77 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -14,7 +14,7 @@ import type { Awareness } from 'y-protocols/awareness';
  */
 import type { WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE } from './config';
 import type { WordPressUserInfo } from './awareness/awareness-types';
-import type { SelectionState } from './selection-utils';
+import type { AwarenessState } from './awareness/awareness-state';
 
 /* globalThis */
 declare global {
@@ -71,11 +71,6 @@ export interface RecordHandlers {
 	getEditedRecord: () => Promise< ObjectData >;
 	refetchRecord: () => Promise< void >;
 	saveRecord: () => Promise< void >;
-	getCurrentUser: () => Promise< WordPressUserInfo >;
-	subscribeToUserSelectionChanges: (
-		yDoc: Y.Doc,
-		setSelectionState: ( selectionState: SelectionState ) => void
-	) => void;
 }
 
 export interface SyncConfig {
@@ -88,6 +83,11 @@ export interface SyncConfig {
 		editedRecord: ObjectData
 	) => ObjectData;
 	supports?: Record< string, true >;
+	createAwareness?: (
+		ydoc: Y.Doc,
+		recordHandlers: RecordHandlers,
+		currentUser: WordPressUserInfo
+	) => AwarenessState | undefined;
 }
 
 export interface SyncManager {
@@ -95,12 +95,17 @@ export interface SyncManager {
 		objectType: ObjectType,
 		objectId: ObjectID
 	) => Record< string, string >;
+	getAwarenessInstance: (
+		objectType: ObjectType,
+		objectId: ObjectID
+	) => AwarenessState | undefined;
 	load: (
 		syncConfig: SyncConfig,
 		objectType: ObjectType,
 		objectId: ObjectID,
 		record: ObjectData,
-		handlers: RecordHandlers
+		handlers: RecordHandlers,
+		currentUser: WordPressUserInfo
 	) => Promise< void >;
 	// undoManager is undefined until the first entity is loaded.
 	undoManager: SyncUndoManager | undefined;
diff --git a/packages/sync/src/user-utils.ts b/packages/sync/src/user-utils.ts
index b84bb24c3c0b48..438940b843c124 100644
--- a/packages/sync/src/user-utils.ts
+++ b/packages/sync/src/user-utils.ts
@@ -1,4 +1,4 @@
-import type { UserInfo } from './awareness/awareness-types';
+import type { UserInfo, WordPressUserInfo } from './awareness/awareness-types';
 import { loadFromLocalStorage, saveToLocalStorage } from './local-storage';
 
 /**
@@ -35,7 +35,7 @@ function generateRandomInt( min: number, max: number ): number {
  * @param existingColors - Colors that are already in use.
  * @return The new user color, in hex format.
  */
-export function getNewUserColor( existingColors: string[] ): string {
+function getNewUserColor( existingColors: string[] ): string {
 	const availableColors = COLOR_PALETTE.filter(
 		( color ) => ! existingColors.includes( color )
 	);
@@ -93,7 +93,7 @@ function generateColorVariation( hexColor: string ): string {
  * Get the browser name from the user agent.
  * @return The browser name.
  */
-export function getBrowserName(): string {
+function getBrowserName(): string {
 	const userAgent = window.navigator.userAgent;
 	let browserName = 'Unknown';
 
@@ -123,6 +123,13 @@ export function getBrowserName(): string {
 	return browserName;
 }
 
+/**
+ * Check if two user infos are equal.
+ *
+ * @param userInfo1 - The first user info.
+ * @param userInfo2 - The second user info.
+ * @return True if the user infos are equal, false otherwise.
+ */
 export function areUserInfosEqual(
 	userInfo1?: UserInfo,
 	userInfo2?: UserInfo
@@ -140,3 +147,22 @@ export function areUserInfosEqual(
 		return value === userInfo2[ key as keyof UserInfo ];
 	} );
 }
+
+/**
+ * Generate a user info object from a current user and a list of existing colors.
+ *
+ * @param currentUser    - The current user.
+ * @param existingColors - The existing colors.
+ * @return The user info object.
+ */
+export function generateUserInfo(
+	currentUser: WordPressUserInfo,
+	existingColors: string[]
+): UserInfo {
+	return {
+		...currentUser,
+		browserType: getBrowserName(),
+		color: getNewUserColor( existingColors ),
+		enteredAt: Date.now(),
+	};
+}

From 2d6ca82a0ad48133809461fdc64c1f2a3d76e43d Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Thu, 22 Jan 2026 15:50:23 +1100
Subject: [PATCH 24/30] Replace undefined awareness test with a mock

---
 packages/sync/src/test/manager.ts | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index c214654697129c..346de8c0c2afb6 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -33,7 +33,20 @@ import type {
 	RecordHandlers,
 	SyncConfig,
 } from '../types';
-import type { WordPressUserInfo } from '../awareness/awareness-types';
+import type {
+	WordPressUserInfo,
+	BaseState,
+} from '../awareness/awareness-types';
+import { AwarenessState } from '../awareness/awareness-state';
+
+/**
+ * A minimal mock awareness class for testing.
+ */
+class MockAwarenessState extends AwarenessState< BaseState > {
+	protected equalityFieldChecks = {
+		userInfo: () => true,
+	};
+}
 
 // Mock dependencies.
 jest.mock( '../providers', () => ( {
@@ -96,8 +109,9 @@ describe( 'SyncManager', () => {
 				}
 			),
 			supports: {},
-			// TODO: Switch this to the generic awareness state implementation instead.
-			createAwareness: jest.fn( () => undefined ),
+			createAwareness: jest.fn(
+				( ydoc: Y.Doc ) => new MockAwarenessState( ydoc )
+			),
 		};
 
 		mockHandlers = {

From 335f32feaeb3935dc90f801bda506549545652b6 Mon Sep 17 00:00:00 2001
From: ingeniumed <ingeniumed@users.noreply.github.com>
Date: Thu, 22 Jan 2026 16:07:41 +1100
Subject: [PATCH 25/30] Fix the tests failures in resolvers

---
 packages/core-data/src/test/resolvers.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/packages/core-data/src/test/resolvers.js b/packages/core-data/src/test/resolvers.js
index 60e56079ee9a7c..fede43b9188bef 100644
--- a/packages/core-data/src/test/resolvers.js
+++ b/packages/core-data/src/test/resolvers.js
@@ -146,6 +146,9 @@ describe( 'getEntityRecord', () => {
 		const resolveSelectWithSync = {
 			getEntitiesConfig: jest.fn( () => ENTITIES_WITH_SYNC ),
 			getEditedEntityRecord: jest.fn(),
+			getCurrentUser: jest.fn( () =>
+				Promise.resolve( { id: 1, name: 'Test User' } )
+			),
 		};
 
 		triggerFetch.mockImplementation( () => POST_RESPONSE );
@@ -172,7 +175,8 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-			}
+			},
+			{ id: 1, name: 'Test User' }
 		);
 	} );
 
@@ -199,6 +203,9 @@ describe( 'getEntityRecord', () => {
 		const resolveSelectWithSync = {
 			getEntitiesConfig: jest.fn( () => ENTITIES_WITH_SYNC ),
 			getEditedEntityRecord: jest.fn(),
+			getCurrentUser: jest.fn( () =>
+				Promise.resolve( { id: 1, name: 'Test User' } )
+			),
 		};
 
 		triggerFetch.mockImplementation( () => POST_RESPONSE );
@@ -225,7 +232,8 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-			}
+			},
+			{ id: 1, name: 'Test User' }
 		);
 	} );
 

From 731eea53ed14536d921b5c118627f9da9143ef91 Mon Sep 17 00:00:00 2001
From: Chris Zarate <chris.zarate@automattic.com>
Date: Thu, 22 Jan 2026 13:09:33 -0700
Subject: [PATCH 26/30] Improve types and keep WordPress domain knowledge out
 of sync package (#74869)

* Improve types and keep WordPress domain knowledge out of sync package

* Fix core-data tests
---
 packages/core-data/src/awareness/config.ts    |  9 +++
 .../{ => awareness}/post-editor-awareness.ts  | 76 +++++++++++------
 packages/core-data/src/awareness/types.ts     | 38 +++++++++
 .../src/awareness/utils.ts}                   | 23 ++----
 packages/core-data/src/entities.js            | 39 ++++-----
 packages/core-data/src/resolvers.js           |  5 +-
 packages/core-data/src/test/resolvers.js      | 12 +--
 packages/core-data/src/types.ts               | 17 +---
 packages/sync/README.md                       | 34 --------
 .../sync/src/awareness/awareness-state.ts     | 23 +++---
 .../sync/src/awareness/awareness-types.ts     | 46 ++---------
 packages/sync/src/config.ts                   | 10 ---
 packages/sync/src/index.ts                    |  8 +-
 packages/sync/src/local-storage.ts            | 53 ------------
 packages/sync/src/manager.ts                  | 26 +++---
 packages/sync/src/test/manager.ts             | 81 +++++--------------
 packages/sync/src/types.ts                    | 15 ++--
 17 files changed, 181 insertions(+), 334 deletions(-)
 create mode 100644 packages/core-data/src/awareness/config.ts
 rename packages/core-data/src/{ => awareness}/post-editor-awareness.ts (73%)
 create mode 100644 packages/core-data/src/awareness/types.ts
 rename packages/{sync/src/user-utils.ts => core-data/src/awareness/utils.ts} (86%)
 delete mode 100644 packages/sync/src/local-storage.ts

diff --git a/packages/core-data/src/awareness/config.ts b/packages/core-data/src/awareness/config.ts
new file mode 100644
index 00000000000000..9874e059650dca
--- /dev/null
+++ b/packages/core-data/src/awareness/config.ts
@@ -0,0 +1,9 @@
+/**
+ * Delay in milliseconds before throttling the cursor position updates.
+ */
+export const AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS = 100;
+
+/**
+ * Delay in milliseconds before updating the cursor position.
+ */
+export const LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS = 5;
diff --git a/packages/core-data/src/post-editor-awareness.ts b/packages/core-data/src/awareness/post-editor-awareness.ts
similarity index 73%
rename from packages/core-data/src/post-editor-awareness.ts
rename to packages/core-data/src/awareness/post-editor-awareness.ts
index ac46c0fc1526c8..39686880002969 100644
--- a/packages/core-data/src/post-editor-awareness.ts
+++ b/packages/core-data/src/awareness/post-editor-awareness.ts
@@ -1,26 +1,27 @@
 /**
  * WordPress dependencies
  */
-import { select, subscribe } from '@wordpress/data';
-import {
-	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
-	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
-	type RecordHandlers,
-	AwarenessState,
-	type UserInfo,
-	areUserInfosEqual,
-} from '@wordpress/sync';
+import { dispatch, select, subscribe } from '@wordpress/data';
+import { AwarenessState, type Y } from '@wordpress/sync';
 // @ts-ignore No exported types for block editor store selectors.
 import { store as blockEditorStore } from '@wordpress/block-editor';
 
 /**
  * Internal dependencies
  */
+import {
+	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
+	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
+} from './config';
+import { STORE_NAME as coreStore } from '../name';
+import { generateUserInfo, areUserInfosEqual } from './utils';
 import {
 	areSelectionsStatesEqual,
 	getSelectionState,
-} from './utils/crdt-user-selections';
-import type { WPBlockSelection, PostEditorState, EditorState } from './types';
+} from '../utils/crdt-user-selections';
+
+import type { WPBlockSelection } from '../types';
+import type { EditorState, PostEditorState } from './types';
 
 export class PostEditorAwareness extends AwarenessState< PostEditorState > {
 	protected equalityFieldChecks = {
@@ -28,20 +29,45 @@ export class PostEditorAwareness extends AwarenessState< PostEditorState > {
 		userInfo: areUserInfosEqual,
 	};
 
-	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
-		super.setUp( recordHandlers, userInfo );
+	public constructor(
+		doc: Y.Doc,
+		private kind: string,
+		private name: string,
+		private postId: number
+	) {
+		super( doc );
+	}
+
+	public setUp(): void {
+		super.setUp();
 
-		this.subscribeToUserSelectionChanges( recordHandlers );
+		this.setCurrentUserInfo();
+		this.subscribeToUserSelectionChanges();
+	}
+
+	/**
+	 * Set the current user info in the local state.
+	 */
+	private setCurrentUserInfo(): void {
+		const states = this.getStates();
+		const otherUserColors = Array.from( states.entries() )
+			.filter(
+				( [ clientId, state ] ) =>
+					state.userInfo && clientId !== this.clientID
+			)
+			.map( ( [ , state ] ) => state.userInfo.color )
+			.filter( Boolean );
+
+		// Get current user info and set it in local state.
+		const currentUser = select( coreStore ).getCurrentUser();
+		const userInfo = generateUserInfo( currentUser, otherUserColors );
+		this.setLocalStateField( 'userInfo', userInfo );
 	}
 
 	/**
 	 * Subscribe to user selection changes and update the selection state.
-	 *
-	 * @param recordHandlers - The record handlers.
 	 */
-	private subscribeToUserSelectionChanges(
-		recordHandlers: RecordHandlers
-	): void {
+	private subscribeToUserSelectionChanges(): void {
 		const {
 			getSelectionStart,
 			getSelectionEnd,
@@ -73,7 +99,6 @@ export class PostEditorAwareness extends AwarenessState< PostEditorState > {
 			// Ensure we update the controlled selection right away, persisting our cursor position locally.
 			const initialPosition = getSelectedBlocksInitialCaretPosition();
 			void this.updateSelectionInEntityRecord(
-				recordHandlers,
 				selectionStart,
 				selectionEnd,
 				initialPosition
@@ -107,13 +132,11 @@ export class PostEditorAwareness extends AwarenessState< PostEditorState > {
 	/**
 	 * Update the entity record with the current user's selection.
 	 *
-	 * @param recordHandlers
 	 * @param selectionStart  - The start position of the selection.
 	 * @param selectionEnd    - The end position of the selection.
 	 * @param initialPosition - The initial position of the selection.
 	 */
 	private async updateSelectionInEntityRecord(
-		recordHandlers: RecordHandlers,
 		selectionStart: WPBlockSelection,
 		selectionEnd: WPBlockSelection,
 		initialPosition: number | null
@@ -134,7 +157,14 @@ export class PostEditorAwareness extends AwarenessState< PostEditorState > {
 			undoIgnore: true,
 		};
 
-		recordHandlers.editRecord( edits, options );
+		// @ts-ignore Types are not provided when using store name instead of store instance.
+		dispatch( coreStore ).editEntityRecord(
+			this.kind,
+			this.name,
+			this.postId,
+			edits,
+			options
+		);
 	}
 
 	/**
diff --git a/packages/core-data/src/awareness/types.ts b/packages/core-data/src/awareness/types.ts
new file mode 100644
index 00000000000000..79ff9621366037
--- /dev/null
+++ b/packages/core-data/src/awareness/types.ts
@@ -0,0 +1,38 @@
+/**
+ * Internal dependencies
+ */
+import type { User } from '../entity-types';
+import type { SelectionState } from '../types';
+
+export type UserInfo = Pick<
+	User< 'view' >,
+	'id' | 'name' | 'slug' | 'avatar_urls'
+> & {
+	browserType: string;
+	color: string;
+	enteredAt: number;
+};
+
+/**
+ * This base state represents the presence of the user. We expect it to be
+ * extended to include additional state describing the user's current activity.
+ * This state must be serializable and compact.
+ */
+export interface BaseState {
+	userInfo: UserInfo;
+}
+
+/**
+ * The editor state includes information about the user's current selection.
+ */
+export interface EditorState {
+	selection: SelectionState;
+}
+
+/**
+ * The post editor state extends the base state with information used to render
+ * presence indicators in the post editor.
+ */
+export interface PostEditorState extends BaseState {
+	editorState?: EditorState;
+}
diff --git a/packages/sync/src/user-utils.ts b/packages/core-data/src/awareness/utils.ts
similarity index 86%
rename from packages/sync/src/user-utils.ts
rename to packages/core-data/src/awareness/utils.ts
index 438940b843c124..74c66293eee1d9 100644
--- a/packages/sync/src/user-utils.ts
+++ b/packages/core-data/src/awareness/utils.ts
@@ -1,5 +1,8 @@
-import type { UserInfo, WordPressUserInfo } from './awareness/awareness-types';
-import { loadFromLocalStorage, saveToLocalStorage } from './local-storage';
+/**
+ * Internal dependencies
+ */
+import type { User } from '../entity-types';
+import type { UserInfo } from './types';
 
 /**
  * The color palette for the user highlight.
@@ -15,8 +18,6 @@ const COLOR_PALETTE = [
 	'#37C5F0', // cyan
 ];
 
-const LOCAL_STORAGE_KEY = 'GUTENBERG_PREFERRED_COLOR_KEY';
-
 /**
  * Generate a random integer between min and max, inclusive.
  *
@@ -40,17 +41,9 @@ function getNewUserColor( existingColors: string[] ): string {
 		( color ) => ! existingColors.includes( color )
 	);
 
-	// TODO: Drop this, and use @wordpress/preferences instead.
-	const preferredColor = loadFromLocalStorage< string | null >(
-		LOCAL_STORAGE_KEY,
-		null
-	);
-
 	let hexColor: string;
 
-	if ( preferredColor && availableColors.includes( preferredColor ) ) {
-		hexColor = preferredColor;
-	} else if ( availableColors.length > 0 ) {
+	if ( availableColors.length > 0 ) {
 		const randomIndex = generateRandomInt( 0, availableColors.length - 1 );
 		hexColor = availableColors[ randomIndex ];
 	} else {
@@ -60,8 +53,6 @@ function getNewUserColor( existingColors: string[] ): string {
 		hexColor = generateColorVariation( baseColor );
 	}
 
-	// TODO: Drop this, and use @wordpress/preferences instead.
-	saveToLocalStorage( LOCAL_STORAGE_KEY, hexColor );
 	return hexColor;
 }
 
@@ -156,7 +147,7 @@ export function areUserInfosEqual(
  * @return The user info object.
  */
 export function generateUserInfo(
-	currentUser: WordPressUserInfo,
+	currentUser: User< 'view' >,
 	existingColors: string[]
 ): UserInfo {
 	return {
diff --git a/packages/core-data/src/entities.js b/packages/core-data/src/entities.js
index 8bf1894b90801b..92467602b00e47 100644
--- a/packages/core-data/src/entities.js
+++ b/packages/core-data/src/entities.js
@@ -9,17 +9,16 @@ import { capitalCase, pascalCase } from 'change-case';
 import apiFetch from '@wordpress/api-fetch';
 import { __unstableSerializeAndClean, parse } from '@wordpress/blocks';
 import { __ } from '@wordpress/i18n';
-import { generateUserInfo } from '@wordpress/sync';
 
 /**
  * Internal dependencies
  */
+import { PostEditorAwareness } from './awareness/post-editor-awareness';
 import { getSyncManager } from './sync';
 import {
 	applyPostChangesToCRDTDoc,
 	getPostChangesFromCRDTDoc,
 } from './utils/crdt';
-import { PostEditorAwareness } from './post-editor-awareness';
 
 export const DEFAULT_ENTITY_KEY = 'id';
 const POST_RAW_ATTRIBUTES = [ 'title', 'excerpt', 'content' ];
@@ -360,6 +359,19 @@ async function loadPostTypeEntities() {
 				applyChangesToCRDTDoc: ( crdtDoc, changes ) =>
 					applyPostChangesToCRDTDoc( crdtDoc, changes, postType ),
 
+				/**
+				 * Create the awareness instance for the entity's CRDT document.
+				 *
+				 * @param {import('@wordpress/sync').CRDTDoc}  ydoc
+				 * @param {import('@wordpress/sync').ObjectID} objectId
+				 * @return {import('@wordpress/sync').AwarenessState} AwarenessState instance
+				 */
+				createAwareness: ( ydoc, objectId ) => {
+					const kind = 'postType';
+					const id = parseInt( objectId, 10 );
+					return new PostEditorAwareness( ydoc, kind, name, id );
+				},
+
 				/**
 				 * Extract changes from a CRDT document that can be used to update the
 				 * local editor state.
@@ -383,29 +395,6 @@ async function loadPostTypeEntities() {
 				supports: {
 					crdtPersistence: true,
 				},
-
-				createAwareness: ( ydoc, recordHandlers, currentUser ) => {
-					const awareness = new PostEditorAwareness( ydoc );
-
-					const states = awareness.getStates();
-					const otherUserColors = Array.from( states.entries() )
-						.filter(
-							( [ clientId, state ] ) =>
-								state.userInfo &&
-								clientId !== awareness.clientID
-						)
-						.map( ( [ , state ] ) => state.userInfo.color )
-						.filter( Boolean );
-
-					const userInfo = generateUserInfo(
-						currentUser,
-						otherUserColors
-					);
-
-					awareness.setUp( recordHandlers, userInfo );
-
-					return awareness;
-				},
 			};
 		}
 
diff --git a/packages/core-data/src/resolvers.js b/packages/core-data/src/resolvers.js
index 1197772713aa64..453733e6a606cd 100644
--- a/packages/core-data/src/resolvers.js
+++ b/packages/core-data/src/resolvers.js
@@ -184,8 +184,6 @@ export const getEntityRecord =
 								transientConfig.read( recordWithTransients );
 						} );
 
-					const currentUser = await resolveSelect.getCurrentUser();
-
 					// Load the entity record for syncing.
 					await getSyncManager()?.load(
 						entityConfig.syncConfig,
@@ -235,8 +233,7 @@ export const getEntityRecord =
 									key
 								);
 							},
-						},
-						currentUser
+						}
 					);
 				}
 			}
diff --git a/packages/core-data/src/test/resolvers.js b/packages/core-data/src/test/resolvers.js
index fede43b9188bef..60e56079ee9a7c 100644
--- a/packages/core-data/src/test/resolvers.js
+++ b/packages/core-data/src/test/resolvers.js
@@ -146,9 +146,6 @@ describe( 'getEntityRecord', () => {
 		const resolveSelectWithSync = {
 			getEntitiesConfig: jest.fn( () => ENTITIES_WITH_SYNC ),
 			getEditedEntityRecord: jest.fn(),
-			getCurrentUser: jest.fn( () =>
-				Promise.resolve( { id: 1, name: 'Test User' } )
-			),
 		};
 
 		triggerFetch.mockImplementation( () => POST_RESPONSE );
@@ -175,8 +172,7 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-			},
-			{ id: 1, name: 'Test User' }
+			}
 		);
 	} );
 
@@ -203,9 +199,6 @@ describe( 'getEntityRecord', () => {
 		const resolveSelectWithSync = {
 			getEntitiesConfig: jest.fn( () => ENTITIES_WITH_SYNC ),
 			getEditedEntityRecord: jest.fn(),
-			getCurrentUser: jest.fn( () =>
-				Promise.resolve( { id: 1, name: 'Test User' } )
-			),
 		};
 
 		triggerFetch.mockImplementation( () => POST_RESPONSE );
@@ -232,8 +225,7 @@ describe( 'getEntityRecord', () => {
 				getEditedRecord: expect.any( Function ),
 				refetchRecord: expect.any( Function ),
 				saveRecord: expect.any( Function ),
-			},
-			{ id: 1, name: 'Test User' }
+			}
 		);
 	} );
 
diff --git a/packages/core-data/src/types.ts b/packages/core-data/src/types.ts
index df42fcee0e6a28..be71e5434fa049 100644
--- a/packages/core-data/src/types.ts
+++ b/packages/core-data/src/types.ts
@@ -1,7 +1,7 @@
 /**
  * External dependencies
  */
-import type { Y, BaseState } from '@wordpress/sync';
+import type { Y } from '@wordpress/sync';
 
 export interface AnyFunction {
 	( ...args: any[] ): any;
@@ -104,18 +104,3 @@ export type SelectionState =
 	| SelectionInOneBlock
 	| SelectionInMultipleBlocks
 	| SelectionWholeBlock;
-
-/**
- * The editor state includes information about the user's current selection.
- */
-export interface EditorState {
-	selection: SelectionState;
-}
-
-/**
- * The post editor state extends the base state with information used to render
- * presence indicators in the post editor.
- */
-export interface PostEditorState extends BaseState {
-	editorState?: EditorState;
-}
diff --git a/packages/sync/README.md b/packages/sync/README.md
index 5b29008f7a8bf3..bda5bc28363bce 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -14,19 +14,6 @@ npm install @wordpress/sync --save
 
 <!-- START TOKEN(Autogenerated API docs) -->
 
-### areUserInfosEqual
-
-Check if two user infos are equal.
-
-_Parameters_
-
--   _userInfo1_ `UserInfo`: - The first user info.
--   _userInfo2_ `UserInfo`: - The second user info.
-
-_Returns_
-
--   `boolean`: True if the user infos are equal, false otherwise.
-
 ### AwarenessState
 
 Abstract class to manage awareness and allow external code to subscribe to state updates.
@@ -35,10 +22,6 @@ _Type_
 
 -   `AwarenessState`
 
-### AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS
-
-Delay in milliseconds before throttling the cursor position updates.
-
 ### CRDT_DOC_META_PERSISTENCE_KEY
 
 CRDT documents can hold meta information in a map. This map exists only in memory and is not synced or persisted. This key can be used to indicate that a (temporary) document has been loaded from persistence.
@@ -67,23 +50,6 @@ The sync manager orchestrates the lifecycle of syncing entity records. It create
 
 Deltas are used to calculate incremental Y.Text updates.
 
-### generateUserInfo
-
-Generate a user info object from a current user and a list of existing colors.
-
-_Parameters_
-
--   _currentUser_ `WordPressUserInfo`: - The current user.
--   _existingColors_ `string[]`: - The existing colors.
-
-_Returns_
-
--   `UserInfo`: The user info object.
-
-### LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS
-
-Delay in milliseconds before updating the cursor position.
-
 ### LOCAL_EDITOR_ORIGIN
 
 Origin string for CRDT document changes originating from the local editor.
diff --git a/packages/sync/src/awareness/awareness-state.ts b/packages/sync/src/awareness/awareness-state.ts
index 3506513e924b30..b211e46abf9a37 100644
--- a/packages/sync/src/awareness/awareness-state.ts
+++ b/packages/sync/src/awareness/awareness-state.ts
@@ -1,11 +1,8 @@
 /**
  * Internal dependencies
  */
-import type { UserInfo } from './awareness-types';
-import type { RecordHandlers } from '../types';
 import {
 	TypedAwareness,
-	type BaseState,
 	type EnhancedState,
 	type EqualityFieldCheck,
 } from './awareness-types';
@@ -21,7 +18,7 @@ interface AwarenessStateChange {
 }
 
 abstract class AwarenessWithEqualityChecks<
-	State extends BaseState = BaseState,
+	State extends object,
 > extends TypedAwareness< State > {
 	/** OVERRIDDEN METHODS */
 
@@ -115,7 +112,7 @@ abstract class AwarenessWithEqualityChecks<
  * state updates.
  */
 export abstract class AwarenessState<
-	State extends BaseState = BaseState,
+	State extends object = {},
 > extends AwarenessWithEqualityChecks< State > {
 	/** CUSTOM PROPERTIES */
 
@@ -152,12 +149,8 @@ export abstract class AwarenessState<
 
 	/**
 	 * Set up the awareness state.
-	 * @param recordHandlers - Record handlers.
-	 * @param userInfo       - User info.
 	 */
-	public setUp( recordHandlers: RecordHandlers, userInfo: UserInfo ): void {
-		this.setLocalStateField( 'userInfo', userInfo );
-
+	public setUp(): void {
 		this.on(
 			'change',
 			( { added, removed, updated }: AwarenessStateChange ) => {
@@ -265,10 +258,12 @@ export abstract class AwarenessState<
 		const updatedStates = new Map< number, EnhancedState< State > >(
 			[ ...this.disconnectedUsers, ...states.keys() ]
 				.filter( ( clientId ) => {
-					// Exclude any users without `userInfo`.
-					// This can happen from the Yjs inspector, which joins the awareness
-					// state without providing user data.
-					return Boolean( this.seenStates.get( clientId )?.userInfo );
+					// Exclude any users with empty awareness state. This can happen from
+					// the Yjs inspector.
+					return (
+						Object.keys( this.seenStates.get( clientId ) ?? {} )
+							.length > 0
+					);
 				} )
 				.map( ( clientId ) => {
 					// The filter above ensures that seenStates has the clientId.
diff --git a/packages/sync/src/awareness/awareness-types.ts b/packages/sync/src/awareness/awareness-types.ts
index fa92cf2a80453d..c4f7cecda691c7 100644
--- a/packages/sync/src/awareness/awareness-types.ts
+++ b/packages/sync/src/awareness/awareness-types.ts
@@ -11,7 +11,7 @@ import { getRecordValue } from '../utils';
 /**
  * Extended Awareness class with typed state accessors.
  */
-export class TypedAwareness< State extends BaseState > extends Awareness {
+export class TypedAwareness< State extends object > extends Awareness {
 	/**
 	 * Get the states from an awareness document.
 	 */
@@ -43,51 +43,17 @@ export class TypedAwareness< State extends BaseState > extends Awareness {
 	}
 }
 
-/**
- * This base user info is a subset of the User interface from @wordpress/core-data.
- *
- * In order to avoid circular dependencies, we define it here instead of importing
- * the User interface from @wordpress/core-data.
- *
- * The avatarUrl is an additional field that is not part of the User interface.
- */
-export interface WordPressUserInfo {
-	id: number;
-	name: string;
-	slug: string;
-	avatar_urls: Record< string, string >;
-}
-
-/**
- * The user info interface extends the base user info with additional fields used for presence
- * indicators.
- */
-export interface UserInfo extends WordPressUserInfo {
-	browserType: string;
-	color: string;
-	enteredAt: number;
-}
-
-/**
- * This base state represents the presence of the user. We expect it to be
- * extended to include additional state describing the user's current activity.
- * This state must be serializable and compact.
- */
-export interface BaseState {
-	userInfo: UserInfo;
-}
-
 /**
  * An enhanced state includes additional metadata about the user's connection
  * that is not appropriate to synchronize via Yjs awareness.
  */
-export type EnhancedState< State extends BaseState > = State & {
+export type EnhancedState< State > = State & {
 	clientId: number;
 	isConnected: boolean;
 	isMe: boolean;
 };
 
-export type EqualityFieldCheck<
-	State extends BaseState,
-	FieldName extends keyof State,
-> = ( value1?: State[ FieldName ], value2?: State[ FieldName ] ) => boolean;
+export type EqualityFieldCheck< State, FieldName extends keyof State > = (
+	value1?: State[ FieldName ],
+	value2?: State[ FieldName ]
+) => boolean;
diff --git a/packages/sync/src/config.ts b/packages/sync/src/config.ts
index 17f65d080cebbf..11eec60c670699 100644
--- a/packages/sync/src/config.ts
+++ b/packages/sync/src/config.ts
@@ -63,13 +63,3 @@ export const WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE = '_crdt_document';
  * Delay in milliseconds before removing a user from presence indicators.
  */
 export const REMOVAL_DELAY_IN_MS = 5000;
-
-/**
- * Delay in milliseconds before updating the cursor position.
- */
-export const LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS = 5;
-
-/**
- * Delay in milliseconds before throttling the cursor position updates.
- */
-export const AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS = 100;
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 7bc9eea7b5e929..7e5eb8c04ed203 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -16,6 +16,7 @@ export * as Y from 'yjs';
  */
 export { default as Delta } from './quill-delta/Delta';
 
+export { AwarenessState } from './awareness/awareness-state';
 export {
 	CRDT_DOC_META_PERSISTENCE_KEY,
 	CRDT_RECORD_MAP_KEY,
@@ -25,11 +26,8 @@ export {
 	LOCAL_EDITOR_ORIGIN,
 	LOCAL_SYNC_MANAGER_ORIGIN,
 	WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE,
-	LOCAL_CURSOR_UPDATE_DEBOUNCE_IN_MS,
-	AWARENESS_CURSOR_UPDATE_THROTTLE_IN_MS,
 } from './config';
 export { createSyncManager } from './manager';
-export type * from './types';
+
 export type * from './awareness/awareness-types';
-export { AwarenessState } from './awareness/awareness-state';
-export { areUserInfosEqual, generateUserInfo } from './user-utils';
+export type * from './types';
diff --git a/packages/sync/src/local-storage.ts b/packages/sync/src/local-storage.ts
deleted file mode 100644
index b1465288020a90..00000000000000
--- a/packages/sync/src/local-storage.ts
+++ /dev/null
@@ -1,53 +0,0 @@
-// TODO: Drop this file, and use @wordpress/preferences instead.
-
-/**
- * Load data from localStorage with error handling
- * @param key          - The localStorage key to read from
- * @param defaultValue - The default value to return if loading fails or key doesn't exist
- * @return The parsed data from localStorage or the default value
- */
-export const loadFromLocalStorage = < T >(
-	key: string,
-	defaultValue: T
-): T => {
-	try {
-		const saved = window?.localStorage?.getItem( key );
-		if ( saved ) {
-			const parsed = JSON.parse( saved ) as T;
-			// If the parsed value is an object (and not null or array), merge with defaultValue
-			if (
-				typeof parsed === 'object' &&
-				parsed !== null &&
-				! Array.isArray( parsed )
-			) {
-				return { ...defaultValue, ...( parsed as Partial< T > ) };
-			}
-			// For primitive values (string, number, boolean, null), return directly
-			return parsed;
-		}
-	} catch ( error ) {
-		// eslint-disable-next-line no-console
-		console.warn(
-			`Failed to load data from localStorage (key: ${ key }):`,
-			error
-		);
-	}
-	return defaultValue;
-};
-
-/**
- * Save data to localStorage with error handling
- * @param key  - The localStorage key to write to
- * @param data - The data to save
- */
-export const saveToLocalStorage = < T >( key: string, data: T ): void => {
-	try {
-		localStorage.setItem( key, JSON.stringify( data ) );
-	} catch ( error ) {
-		// eslint-disable-next-line no-console
-		console.warn(
-			`Failed to save data to localStorage (key: ${ key }):`,
-			error
-		);
-	}
-};
diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index ef999b44d17fe8..e040e499be839f 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -29,14 +29,13 @@ import type {
 import { createUndoManager } from './undo-manager';
 import { createYjsDoc } from './utils';
 import type { AwarenessState } from './awareness/awareness-state';
-import type { WordPressUserInfo } from './awareness/awareness-types';
 
 interface EntityState {
+	awareness?: AwarenessState;
 	handlers: RecordHandlers;
 	objectId: ObjectID;
 	objectType: ObjectType;
 	syncConfig: SyncConfig;
-	awareness?: AwarenessState;
 	unload: () => void;
 	ydoc: CRDTDoc;
 }
@@ -83,20 +82,18 @@ export function createSyncManager(): SyncManager {
 	/**
 	 * Load an entity for syncing and manage its lifecycle.
 	 *
-	 * @param {SyncConfig}        syncConfig  Sync configuration for the object type.
-	 * @param {ObjectType}        objectType  Object type.
-	 * @param {ObjectID}          objectId    Object ID.
-	 * @param {ObjectData}        record      Entity record representing this object type.
-	 * @param {RecordHandlers}    handlers    Handlers for updating and fetching the record.
-	 * @param {WordPressUserInfo} currentUser Current user.
+	 * @param {SyncConfig}     syncConfig Sync configuration for the object type.
+	 * @param {ObjectType}     objectType Object type.
+	 * @param {ObjectID}       objectId   Object ID.
+	 * @param {ObjectData}     record     Entity record representing this object type.
+	 * @param {RecordHandlers} handlers   Handlers for updating and fetching the record.
 	 */
 	async function loadEntity(
 		syncConfig: SyncConfig,
 		objectType: ObjectType,
 		objectId: ObjectID,
 		record: ObjectData,
-		handlers: RecordHandlers,
-		currentUser: WordPressUserInfo
+		handlers: RecordHandlers
 	): Promise< void > {
 		const providerCreators = getProviderCreators();
 
@@ -124,11 +121,8 @@ export function createSyncManager(): SyncManager {
 		};
 
 		// If the sync config supports awareness, create it.
-		const awareness = syncConfig.createAwareness?.(
-			ydoc,
-			handlers,
-			currentUser
-		);
+		const awareness = syncConfig.createAwareness?.( ydoc, objectId );
+		awareness?.setUp();
 
 		// When the CRDT document is updated by an UndoManager or a connection (not
 		// a local origin), update the local store.
@@ -175,11 +169,11 @@ export function createSyncManager(): SyncManager {
 		undoManager.addToScope( recordMap );
 
 		const entityState: EntityState = {
+			awareness,
 			handlers,
 			objectId,
 			objectType,
 			syncConfig,
-			awareness,
 			unload,
 			ydoc,
 		};
diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index 346de8c0c2afb6..0120fc0ed54ad7 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -33,16 +33,12 @@ import type {
 	RecordHandlers,
 	SyncConfig,
 } from '../types';
-import type {
-	WordPressUserInfo,
-	BaseState,
-} from '../awareness/awareness-types';
 import { AwarenessState } from '../awareness/awareness-state';
 
 /**
  * A minimal mock awareness class for testing.
  */
-class MockAwarenessState extends AwarenessState< BaseState > {
+class MockAwarenessState extends AwarenessState {
 	protected equalityFieldChecks = {
 		userInfo: () => true,
 	};
@@ -59,7 +55,6 @@ describe( 'SyncManager', () => {
 	let mockProviderCreator: jest.Mock< ProviderCreator >;
 	let mockProviderResult: ProviderCreatorResult;
 	let mockRecord: ObjectData;
-	let mockCurrentUser: WordPressUserInfo;
 	let mockSyncConfig: jest.MockedObject< SyncConfig >;
 
 	beforeEach( () => {
@@ -71,17 +66,6 @@ describe( 'SyncManager', () => {
 			title: 'Test Post',
 		};
 
-		mockCurrentUser = {
-			id: 1,
-			name: 'Test User',
-			slug: 'test-user',
-			avatar_urls: {
-				'24': 'https://example.com/avatar.jpg',
-				'48': 'https://example.com/avatar-48.jpg',
-				'96': 'https://example.com/avatar-96.jpg',
-			},
-		};
-
 		mockProviderResult = {
 			destroy: jest.fn(),
 		};
@@ -144,8 +128,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			// Verify that applyChangesToCRDTDoc was called with the record data
@@ -163,8 +146,7 @@ describe( 'SyncManager', () => {
 				'postType/post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			expect( mockProviderCreator ).toHaveBeenCalledTimes( 1 );
@@ -186,8 +168,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			expect(
@@ -204,8 +185,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			await manager.load(
@@ -213,8 +193,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			// Should only be called once despite two load attempts
@@ -235,8 +214,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				record1,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			await manager.load(
@@ -244,8 +222,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'456',
 				record2,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			expect(
@@ -293,8 +270,7 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					mockRecord,
-					mockHandlers,
-					mockCurrentUser
+					mockHandlers
 				);
 
 				// Current record should be applied as changes since the persisted doc does not exist.
@@ -329,8 +305,7 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers,
-					mockCurrentUser
+					mockHandlers
 				);
 
 				// Changes should NOT be applied since the persisted doc is valid.
@@ -369,8 +344,7 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers,
-					mockCurrentUser
+					mockHandlers
 				);
 
 				// Changes should be applied for the invalidated properties.
@@ -410,8 +384,7 @@ describe( 'SyncManager', () => {
 					'post',
 					'123',
 					record,
-					mockHandlers,
-					mockCurrentUser
+					mockHandlers
 				);
 
 				// Current record should be applied since the persisted doc does not exist.
@@ -442,8 +415,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			manager.unload( 'post', '123' );
@@ -467,8 +439,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			manager.unload( 'post', '123' );
@@ -480,8 +451,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			expect(
@@ -498,8 +468,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			await manager.load(
@@ -507,8 +476,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'456',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			manager.unload( 'post', '123' );
@@ -546,8 +514,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			jest.clearAllMocks();
@@ -600,8 +567,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			// Get the captured Y.Doc
@@ -645,8 +611,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			jest.clearAllMocks();
@@ -694,8 +659,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			// Clear calls of editRecord, which is called during load.
@@ -744,8 +708,7 @@ describe( 'SyncManager', () => {
 				'post',
 				'123',
 				mockRecord,
-				mockHandlers,
-				mockCurrentUser
+				mockHandlers
 			);
 
 			// Clear calls of editRecord, which is called during load.
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index aaa8be713f2c77..f3045cb7eb8469 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -12,9 +12,8 @@ import type { Awareness } from 'y-protocols/awareness';
 /**
  * Internal dependencies
  */
-import type { WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE } from './config';
-import type { WordPressUserInfo } from './awareness/awareness-types';
 import type { AwarenessState } from './awareness/awareness-state';
+import type { WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE } from './config';
 
 /* globalThis */
 declare global {
@@ -78,16 +77,15 @@ export interface SyncConfig {
 		ydoc: Y.Doc,
 		changes: Partial< ObjectData >
 	) => void;
+	createAwareness?: (
+		ydoc: Y.Doc,
+		objectId: ObjectID
+	) => AwarenessState | undefined;
 	getChangesFromCRDTDoc: (
 		ydoc: Y.Doc,
 		editedRecord: ObjectData
 	) => ObjectData;
 	supports?: Record< string, true >;
-	createAwareness?: (
-		ydoc: Y.Doc,
-		recordHandlers: RecordHandlers,
-		currentUser: WordPressUserInfo
-	) => AwarenessState | undefined;
 }
 
 export interface SyncManager {
@@ -104,8 +102,7 @@ export interface SyncManager {
 		objectType: ObjectType,
 		objectId: ObjectID,
 		record: ObjectData,
-		handlers: RecordHandlers,
-		currentUser: WordPressUserInfo
+		handlers: RecordHandlers
 	) => Promise< void >;
 	// undoManager is undefined until the first entity is loaded.
 	undoManager: SyncUndoManager | undefined;

From e8af2461ba77cd264994fbaaedf34d71f3de123c Mon Sep 17 00:00:00 2001
From: chriszarate <chris.zarate@automattic.com>
Date: Thu, 22 Jan 2026 13:54:13 -0700
Subject: [PATCH 27/30] Remove unnecessary exports

---
 packages/sync/README.md    | 8 --------
 packages/sync/src/index.ts | 2 --
 2 files changed, 10 deletions(-)

diff --git a/packages/sync/README.md b/packages/sync/README.md
index bda5bc28363bce..cba9c4e40bf4d2 100644
--- a/packages/sync/README.md
+++ b/packages/sync/README.md
@@ -58,14 +58,6 @@ Origin string for CRDT document changes originating from the local editor.
 
 Origin string for CRDT document changes originating from the sync manager.
 
-### TypedAwareness
-
-Extended Awareness class with typed state accessors.
-
-_Type_
-
--   `TypedAwareness`
-
 ### WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE
 
 WordPress meta key used to persist the CRDT document for an entity.
diff --git a/packages/sync/src/index.ts b/packages/sync/src/index.ts
index 7e5eb8c04ed203..4fbcf47ca5996b 100644
--- a/packages/sync/src/index.ts
+++ b/packages/sync/src/index.ts
@@ -28,6 +28,4 @@ export {
 	WORDPRESS_META_KEY_FOR_CRDT_DOC_PERSISTENCE,
 } from './config';
 export { createSyncManager } from './manager';
-
-export type * from './awareness/awareness-types';
 export type * from './types';

From daa079a568ef59c8c924b85c649595463a8046fc Mon Sep 17 00:00:00 2001
From: chriszarate <chris.zarate@automattic.com>
Date: Thu, 22 Jan 2026 13:54:42 -0700
Subject: [PATCH 28/30] Rename getAwarenessInstance => getAwareness for
 symmetry

---
 packages/sync/src/manager.ts | 4 ++--
 packages/sync/src/types.ts   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/sync/src/manager.ts b/packages/sync/src/manager.ts
index e040e499be839f..b45025772bb1c6 100644
--- a/packages/sync/src/manager.ts
+++ b/packages/sync/src/manager.ts
@@ -225,7 +225,7 @@ export function createSyncManager(): SyncManager {
 	 * @param {ObjectID}   objectId   Object ID.
 	 * @return {AwarenessState | undefined} The awareness instance, or undefined if not supported.
 	 */
-	function getAwarenessInstance(
+	function getAwareness(
 		objectType: ObjectType,
 		objectId: ObjectID
 	): AwarenessState | undefined {
@@ -440,7 +440,7 @@ export function createSyncManager(): SyncManager {
 
 	return {
 		createMeta: createEntityMeta,
-		getAwarenessInstance,
+		getAwareness,
 		load: loadEntity,
 		// Use getter to ensure we always return the current value of `undoManager`.
 		get undoManager(): SyncUndoManager | undefined {
diff --git a/packages/sync/src/types.ts b/packages/sync/src/types.ts
index f3045cb7eb8469..784c5bc6d71785 100644
--- a/packages/sync/src/types.ts
+++ b/packages/sync/src/types.ts
@@ -93,7 +93,7 @@ export interface SyncManager {
 		objectType: ObjectType,
 		objectId: ObjectID
 	) => Record< string, string >;
-	getAwarenessInstance: (
+	getAwareness: (
 		objectType: ObjectType,
 		objectId: ObjectID
 	) => AwarenessState | undefined;

From fa964edec81555c9f84a1460a7353a8baaa0cb50 Mon Sep 17 00:00:00 2001
From: chriszarate <chris.zarate@automattic.com>
Date: Thu, 22 Jan 2026 13:55:19 -0700
Subject: [PATCH 29/30] Remove vestial userInfo reference

---
 packages/sync/src/test/manager.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/packages/sync/src/test/manager.ts b/packages/sync/src/test/manager.ts
index 0120fc0ed54ad7..3f34efdb725daf 100644
--- a/packages/sync/src/test/manager.ts
+++ b/packages/sync/src/test/manager.ts
@@ -39,9 +39,7 @@ import { AwarenessState } from '../awareness/awareness-state';
  * A minimal mock awareness class for testing.
  */
 class MockAwarenessState extends AwarenessState {
-	protected equalityFieldChecks = {
-		userInfo: () => true,
-	};
+	protected equalityFieldChecks = {};
 }
 
 // Mock dependencies.

From ec820f4b47317e2a0d2d9bc76e5f7274a2d7ee0f Mon Sep 17 00:00:00 2001
From: chriszarate <chris.zarate@automattic.com>
Date: Thu, 22 Jan 2026 13:57:36 -0700
Subject: [PATCH 30/30] Relocate selection types and use YMapWrap

---
 packages/core-data/src/awareness/types.ts     |   2 +-
 packages/core-data/src/types.ts               |  91 ---------------
 .../src/utils/crdt-user-selections.ts         | 107 ++++++++++++++----
 3 files changed, 85 insertions(+), 115 deletions(-)

diff --git a/packages/core-data/src/awareness/types.ts b/packages/core-data/src/awareness/types.ts
index 79ff9621366037..9e2061a515af92 100644
--- a/packages/core-data/src/awareness/types.ts
+++ b/packages/core-data/src/awareness/types.ts
@@ -1,8 +1,8 @@
 /**
  * Internal dependencies
  */
+import type { SelectionState } from '../utils/crdt-user-selections';
 import type { User } from '../entity-types';
-import type { SelectionState } from '../types';
 
 export type UserInfo = Pick<
 	User< 'view' >,
diff --git a/packages/core-data/src/types.ts b/packages/core-data/src/types.ts
index be71e5434fa049..dac976505a8f2d 100644
--- a/packages/core-data/src/types.ts
+++ b/packages/core-data/src/types.ts
@@ -1,8 +1,3 @@
-/**
- * External dependencies
- */
-import type { Y } from '@wordpress/sync';
-
 export interface AnyFunction {
 	( ...args: any[] ): any;
 }
@@ -18,89 +13,3 @@ export interface WPSelection {
 	selectionEnd: WPBlockSelection;
 	selectionStart: WPBlockSelection;
 }
-
-/**
- * Convenience types to manage block values with a clientId, attributes, and innerBlocks.
- */
-export type BlockInnerBlocks = Y.Array< SelectableBlock >;
-type BlockClientId = string;
-type BlockAttributes = Y.Map< Y.Text >;
-
-/**
- * A block that can be selected.
- */
-export type SelectableBlock = Y.Map<
-	BlockClientId | BlockAttributes | BlockInnerBlocks
->;
-
-/**
- * The type of selection.
- */
-export enum SelectionType {
-	None = 'none',
-	Cursor = 'cursor',
-	SelectionInOneBlock = 'selection-in-one-block',
-	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
-	WholeBlock = 'whole-block',
-}
-
-/**
- * The position of the cursor.
- */
-export type CursorPosition = {
-	relativePosition: Y.RelativePosition;
-
-	// Also store the absolute offset index of the cursor from the perspective
-	// of the user who is updating the selection.
-	//
-	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
-	// on relativePosition for the most up-to-date positioning.
-	//
-	// This is used because local Y.Text changes (e.g. adding or deleting a character)
-	// can result in the same relative position if it is pinned to an unchanged
-	// character. With both of these values as editor state, a change in perceived
-	// position will always result in a redraw.
-	absoluteOffset: number;
-};
-
-export type SelectionNone = {
-	// The user has not made a selection.
-	type: SelectionType.None;
-};
-
-export type SelectionCursor = {
-	// The user has a cursor position in a block with no text highlighted.
-	type: SelectionType.Cursor;
-	blockId: string;
-	cursorPosition: CursorPosition;
-};
-
-export type SelectionInOneBlock = {
-	// The user has highlighted text in a single block.
-	type: SelectionType.SelectionInOneBlock;
-	blockId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionInMultipleBlocks = {
-	// The user has highlighted text over multiple blocks.
-	type: SelectionType.SelectionInMultipleBlocks;
-	blockStartId: string;
-	blockEndId: string;
-	cursorStartPosition: CursorPosition;
-	cursorEndPosition: CursorPosition;
-};
-
-export type SelectionWholeBlock = {
-	// The user has a non-text block selected, like an image block.
-	type: SelectionType.WholeBlock;
-	blockId: string;
-};
-
-export type SelectionState =
-	| SelectionNone
-	| SelectionCursor
-	| SelectionInOneBlock
-	| SelectionInMultipleBlocks
-	| SelectionWholeBlock;
diff --git a/packages/core-data/src/utils/crdt-user-selections.ts b/packages/core-data/src/utils/crdt-user-selections.ts
index 45ca50dc1706d2..e8362cdc8df339 100644
--- a/packages/core-data/src/utils/crdt-user-selections.ts
+++ b/packages/core-data/src/utils/crdt-user-selections.ts
@@ -6,18 +6,82 @@ import { Y, CRDT_RECORD_MAP_KEY } from '@wordpress/sync';
 /**
  * Internal dependencies
  */
-import type {
-	WPBlockSelection,
-	SelectionState,
-	SelectableBlock,
-	CursorPosition,
-	SelectionNone,
-	SelectionCursor,
-	SelectionInOneBlock,
-	SelectionInMultipleBlocks,
-	SelectionWholeBlock,
-} from '../types';
-import { SelectionType, type BlockInnerBlocks } from '../types';
+import type { YPostRecord } from './crdt';
+import type { YBlock, YBlocks } from './crdt-blocks';
+import { getRootMap } from './crdt-utils';
+import type { WPBlockSelection } from '../types';
+
+/**
+ * The type of selection.
+ */
+export enum SelectionType {
+	None = 'none',
+	Cursor = 'cursor',
+	SelectionInOneBlock = 'selection-in-one-block',
+	SelectionInMultipleBlocks = 'selection-in-multiple-blocks',
+	WholeBlock = 'whole-block',
+}
+
+/**
+ * The position of the cursor.
+ */
+export type CursorPosition = {
+	relativePosition: Y.RelativePosition;
+
+	// Also store the absolute offset index of the cursor from the perspective
+	// of the user who is updating the selection.
+	//
+	// Do not use this value directly, instead use `createAbsolutePositionFromRelativePosition()`
+	// on relativePosition for the most up-to-date positioning.
+	//
+	// This is used because local Y.Text changes (e.g. adding or deleting a character)
+	// can result in the same relative position if it is pinned to an unchanged
+	// character. With both of these values as editor state, a change in perceived
+	// position will always result in a redraw.
+	absoluteOffset: number;
+};
+
+export type SelectionNone = {
+	// The user has not made a selection.
+	type: SelectionType.None;
+};
+
+export type SelectionCursor = {
+	// The user has a cursor position in a block with no text highlighted.
+	type: SelectionType.Cursor;
+	blockId: string;
+	cursorPosition: CursorPosition;
+};
+
+export type SelectionInOneBlock = {
+	// The user has highlighted text in a single block.
+	type: SelectionType.SelectionInOneBlock;
+	blockId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionInMultipleBlocks = {
+	// The user has highlighted text over multiple blocks.
+	type: SelectionType.SelectionInMultipleBlocks;
+	blockStartId: string;
+	blockEndId: string;
+	cursorStartPosition: CursorPosition;
+	cursorEndPosition: CursorPosition;
+};
+
+export type SelectionWholeBlock = {
+	// The user has a non-text block selected, like an image block.
+	type: SelectionType.WholeBlock;
+	blockId: string;
+};
+
+export type SelectionState =
+	| SelectionNone
+	| SelectionCursor
+	| SelectionInOneBlock
+	| SelectionInMultipleBlocks
+	| SelectionWholeBlock;
 
 /**
  * Converts WordPress block editor selection to a SelectionState.
@@ -32,8 +96,8 @@ export function getSelectionState(
 	selectionEnd: WPBlockSelection,
 	yDoc: Y.Doc
 ): SelectionState {
-	const ydoc = yDoc.getMap( CRDT_RECORD_MAP_KEY );
-	const yBlocks = ydoc.get( 'blocks' ) as Y.Array< SelectableBlock >;
+	const ymap = getRootMap< YPostRecord >( yDoc, CRDT_RECORD_MAP_KEY );
+	const yBlocks = ymap.get( 'blocks' ) ?? new Y.Array< YBlock >();
 
 	const isSelectionEmpty = Object.keys( selectionStart ).length === 0;
 	const noSelection: SelectionNone = {
@@ -122,7 +186,7 @@ export function getSelectionState(
  */
 function getCursorPosition(
 	selection: WPBlockSelection,
-	blocks: Y.Array< SelectableBlock >
+	blocks: YBlocks
 ): CursorPosition | null {
 	const block = findBlockByClientId( selection.clientId, blocks );
 	if ( ! block ) {
@@ -152,20 +216,17 @@ function getCursorPosition(
  */
 function findBlockByClientId(
 	blockId: string,
-	blocks: Y.Array< SelectableBlock >
-): SelectableBlock | null {
+	blocks: YBlocks
+): YBlock | null {
 	for ( const block of blocks ) {
 		if ( block.get( 'clientId' ) === blockId ) {
 			return block;
 		}
 
-		const innerBlocks = block.get( 'innerBlocks' ) as BlockInnerBlocks;
+		const innerBlocks = block.get( 'innerBlocks' );
 
-		if ( innerBlocks.length > 0 ) {
-			const innerBlock = findBlockByClientId(
-				blockId,
-				block.get( 'innerBlocks' ) as Y.Array< SelectableBlock >
-			);
+		if ( innerBlocks && innerBlocks.length > 0 ) {
+			const innerBlock = findBlockByClientId( blockId, innerBlocks );
 
 			if ( innerBlock ) {
 				return innerBlock;