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Cursor chat

apps/docs/content/sdk-features/cursor-chat.mdx

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Cursor chat lets users send short messages that appear as bubbles near their cursor. It's designed for quick, ephemeral communication during collaborative sessions: a fast "look here" or "nice work" that doesn't interrupt the canvas workflow.

Cursor chat only appears when collaboration UI is enabled, which means the store has to be collaborative. The simplest way to get one is useSyncDemo:

tsx
import { useSyncDemo } from '@tldraw/sync'
import { Tldraw } from 'tldraw'
import 'tldraw/tldraw.css'

export default function App() {
	const store = useSyncDemo({ roomId: 'my-cursor-chat-room' })

	return (
		<div style={{ position: 'fixed', inset: 0 }}>
			<Tldraw
				store={store}
				onMount={(editor) => {
					// Show a message bubble at the cursor
					editor.updateInstanceState({ chatMessage: 'Hello from the canvas!' })
				}}
			/>
		</div>
	)
}

On desktop, users press / to open the chat input, type their message (up to 64 characters), and press Enter to send. The message follows their cursor. Once the input closes, the message stays visible for two seconds and then clears.

Chat state

Chat state lives in instance state with two properties:

PropertyTypeDescription
isChattingbooleanWhether the user is actively typing
chatMessagestringThe current message (max 64 characters)

Read the current state with Editor#getInstanceState:

tsx
const { isChatting, chatMessage } = editor.getInstanceState()

Update it with Editor#updateInstanceState:

tsx
// Start chatting
editor.updateInstanceState({ isChatting: true })

// Update the message
editor.updateInstanceState({ chatMessage: 'Looking at this shape' })

// Stop chatting and clear the message
editor.updateInstanceState({ isChatting: false, chatMessage: '' })

Both properties are ephemeral—they don't persist to storage or survive page reloads.

How it works

When a user starts chatting:

  1. The CursorChatBubble component renders an input field at the cursor position
  2. The input tracks the cursor via pointermove events
  3. As the user types, chatMessage updates in instance state
  4. When they press Enter with text in the input, the input clears and the message becomes its placeholder; the input stays open for another message
  5. When they press Escape, press Enter with an empty input, or the input loses focus, isChatting becomes false
  6. The message stays visible for 2 seconds, then clears automatically

While the input is open, chat times out after 5 seconds of inactivity.

Keyboard shortcuts

The default keyboard action for cursor chat is /. You can find it under the action ID open-cursor-chat. The action is only registered when collaboration UI is enabled, and the default context menu shows it as CursorChatItem:

tsx
import { Tldraw, useActions } from 'tldraw'

function ChatButton() {
	const actions = useActions()

	return (
		<button onClick={() => actions['open-cursor-chat'].onSelect('menu')}>Open cursor chat</button>
	)
}

Inside the chat input:

KeyAction
EnterSend the message (if content exists) or stop chatting (if input empty)
EscapeStop chatting

Presence synchronization

In multiplayer sessions, chat messages synchronize automatically through presence records. The chatMessage field in TLInstancePresence contains the message other users see:

tsx
import { createUserId, InstancePresenceRecordType } from 'tldraw'

// Inside onMount: create a remote user's presence with a chat message
const peerPresence = InstancePresenceRecordType.create({
	id: InstancePresenceRecordType.createId(editor.store.id),
	currentPageId: editor.getCurrentPageId(),
	userId: createUserId('peer-1'),
	userName: 'Alice',
	cursor: { x: 100, y: 200, type: 'default', rotation: 0 },
	chatMessage: 'Check out this arrow!',
})

editor.store.mergeRemoteChanges(() => {
	editor.store.put([peerPresence])
})

The presence derivation includes the local user's chatMessage from instance state, so changes broadcast to other users without any extra work.

Customizing the chat bubble

You can replace the default chat bubble by providing a custom CursorChatBubble component through TLUiComponents. The slot is only rendered when collaboration UI is enabled, so this example needs a collaborative store too:

tsx
import { useSyncDemo } from '@tldraw/sync'
import { Tldraw, TLUiComponents, useEditor, track } from 'tldraw'
import 'tldraw/tldraw.css'

const CustomCursorChat = track(function CustomCursorChat() {
	const editor = useEditor()
	const { isChatting, chatMessage } = editor.getInstanceState()

	if (!isChatting && !chatMessage) return null

	return (
		<div
			style={{
				position: 'fixed',
				bottom: 20,
				left: '50%',
				transform: 'translateX(-50%)',
				padding: '8px 16px',
				background: editor.user.getColor(),
				borderRadius: 8,
				color: 'white',
			}}
		>
			{isChatting ? 'Typing...' : chatMessage}
		</div>
	)
})

const components: TLUiComponents = {
	CursorChatBubble: CustomCursorChat,
}

export default function App() {
	const store = useSyncDemo({ roomId: 'my-cursor-chat-room' })
	return (
		<div style={{ position: 'fixed', inset: 0 }}>
			<Tldraw store={store} components={components} />
		</div>
	)
}

Remote users' chat messages render as part of the collaborator cursor, in the DOM cursor layer. To customize how they appear, replace the CollaboratorCursor component. See Cursors for details.

Availability

Cursor chat requires:

  • Collaboration enabled (editor.store.props.collaboration !== undefined)
  • A non-touch device (disabled on mobile/tablet)

Setting isChatting isn't gated, but the bubble won't render without both, so check availability before triggering chat programmatically:

tsx
const hasCollaboration = editor.store.props.collaboration !== undefined
const isTouchDevice = editor.getInstanceState().isCoarsePointer

if (hasCollaboration && !isTouchDevice) {
	editor.updateInstanceState({ isChatting: true })
}
  • Cursors — Cursor types, colors, and collaborator cursor customization
  • Collaboration — Presence synchronization and multiplayer setup
  • User preferences — User colors and identity
  • User presence — Display collaborator cursors and chat messages