import { PopoverDemos, UseFullscreenDemos, UseMouseDemos } from '@docs/demos'; import { Layout } from '@/layout'; import { MDX_DATA } from '@/mdx'; import packageJson from '../../../../../package.json';

export default Layout(MDX_DATA.EightToNine);

8.x → 9.x migration guide

Migrate with LLM agents

You can use LLM agents to assist with the migration from 8.x to 9.x. The LLM documentation includes all breaking changes and migration steps in a format optimized for AI coding tools. Copy the link to the md documentation file and ask your AI agent to perform the migration for you.

Prerequisites

Mantine 9.x requires React 19.2 or later. If your project uses an older React version, you need to update it before migrating to Mantine 9.x. If you cannot update React to 19.2+ yet, you can continue using Mantine 8.x until you are ready to update React and migrate to Mantine 9.x.

Update dependencies

Update all @mantine/* packages to version {packageJson.version}
If you use @mantine/tiptap package, update all @tiptap/* packages to the latest 3.x version
If you use @mantine/charts package, update recharts to the latest 3.x version

use-form TransformValues type

The second generic type of the useForm hook is now the type of transformed values instead of the transform function type. New usage example:

tsx

import { useForm } from '@mantine/form';

interface FormValues {
  name: string;
  locationId: string;
}

interface TransformedValues {
  name: string;
  locationId: number;
}

function Demo() {
  const form = useForm<FormValues, TransformedValues>({
    mode: 'uncontrolled',
    initialValues: {
      name: '',
      locationId: '2',
    },

    transformValues: (values) => ({
      ...values,
      locationId: Number(values.locationId),
    }),
  });
}

Text color prop

The color prop of the Text and Anchor components was removed. Use the c style prop instead:

tsx

import { Text } from '@mantine/core';

// ❌ No longer works
function Demo() {
  return <Text color="red">Text</Text>;
}

// ✅ Use the c style prop
function Demo() {
  return <Text c="red">Text</Text>;
}

Light variant color changes

In Mantine 9, the light variant CSS variables were changed to use solid color values instead of transparency. If you need to keep 8.x behavior during migration, use v8CssVariablesResolver:

tsx

import {
  Button,
  MantineProvider,
  v8CssVariablesResolver,
} from '@mantine/core';

function Demo() {
  return (
    <MantineProvider cssVariablesResolver={v8CssVariablesResolver}>
      <Button variant="light" color="blue.6">
        Uses 8.x light variant colors
      </Button>
    </MantineProvider>
  );
}

Form resolvers

In 9.x, @mantine/form has built-in support for Standard Schema. If your schema library supports Standard Schema (Zod v4, Valibot, ArkType), use the built-in schemaResolver instead of a dedicated resolver package:

Example with 8.x:

tsx

import { z } from 'zod';
// ❌ No longer works; zodResolver is not exported from @mantine/form
import { useForm, zodResolver } from '@mantine/form';

const schema = z.object({
  email: z.string().email({ message: 'Invalid email' }),
});

const form = useForm({
  initialValues: { email: '' },
  validate: zodResolver(schema),
});

Example with 9.x using Standard Schema (recommended):

tsx

import { z } from 'zod/v4';
import { useForm, schemaResolver } from '@mantine/form';

const schema = z.object({
  email: z.email({ error: 'Invalid email' }),
});

const form = useForm({
  initialValues: { email: '' },
  validate: schemaResolver(schema, { sync: true }),
});

TypographyStylesProvider

The TypographyStylesProvider component was renamed to Typography:

tsx

// ❌ No longer works
import { TypographyStylesProvider } from '@mantine/core';

// ✅ Use the Typography component
import { Typography } from '@mantine/core';

The Popover and Tooltip components no longer accept the positionDependencies prop; it is no longer required – the position is now calculated automatically.

tsx

import { Popover } from '@mantine/core';

// ❌ positionDependencies is no longer needed
function Demo(props) {
  return (
    <Popover position="top" positionDependencies={[props.a, props.b]}>
    </Popover>
  );
}

// ✅ The position is recalculated automatically
function Demo(props) {
  return (
    <Popover position="top">
    </Popover>
  );
}

use-fullscreen hook changes

The use-fullscreen hook was split into two hooks: useFullscreenElement and useFullscreenDocument. This change was required to fix a stale ref issue in the previous implementation.

New usage with the document element:

New usage with a custom target element:

use-mouse hook changes

The use-mouse hook was split into two hooks: useMouse and useMousePosition. This change was required to fix a stale ref issue in the previous implementation.

Previous usage with the document element:

tsx

import { Text, Code } from '@mantine/core';
import { useMouse } from '@mantine/hooks';

function Demo() {
  const { x, y } = useMouse();

  return (
    <Text ta="center">
      Mouse coordinates <Code>{`{ x: ${x}, y: ${y} }`}</Code>
    </Text>
  );
}

New usage with document:

use-mutation-observer hook changes

The use-mutation-observer hook now uses the new callback ref approach. This change was required to fix stale ref issues and improve compatibility with dynamic node changes.

Previous usage (8.x):

tsx

import { useMutationObserver } from '@mantine/hooks';

useMutationObserver(
  (mutations) => console.log(mutations),
  { childList: true },
  // ❌ The third argument is no longer supported; use `useMutationObserverTarget` instead
  document.getElementById('external-element')
);

New usage (9.x):

tsx

import { useMutationObserverTarget } from '@mantine/hooks';

// ✅ Rename the hook to `useMutationObserverTarget`
useMutationObserverTarget(
  (mutations) => console.log(mutations),
  { childList: true },
  // ✅ Pass the target element as the third argument
  document.getElementById('external-element')
);

Rename hooks types

@mantine/hooks types were renamed for consistency; rename them in your codebase:

UseScrollSpyReturnType → UseScrollSpyReturnValue
StateHistory → UseStateHistoryValue
OS → UseOSReturnValue

Collapse in -> expanded

The Collapse component now uses the expanded prop instead of in:

tsx

import { Collapse } from '@mantine/core';

// ❌ No longer works
function Demo() {
  return (
    <Collapse in={false}>
    </Collapse>
  );
}

// ✅ Use the expanded prop
function Demo() {
  return (
    <Collapse expanded={false}>
    </Collapse>
  );
}

Spoiler initialState -> defaultExpanded

The Spoiler component's initialState prop was renamed to defaultExpanded for consistency with other Mantine components:

tsx

import { Spoiler } from '@mantine/core';

// ❌ No longer works
function Demo() {
  return (
    <Spoiler initialState={false} showLabel="Show" hideLabel="Hide">
    </Spoiler>
  );
}

// ✅ Use the defaultExpanded prop
function Demo() {
  return (
    <Spoiler defaultExpanded={false} showLabel="Show" hideLabel="Hide">
    </Spoiler>
  );
}

Grid gutter -> gap

The Grid component gutter prop was renamed to gap for consistency with other layout components (like Flex and SimpleGrid). Additionally, new rowGap and columnGap props were added to allow separate control of vertical and horizontal spacing:

tsx

import { Grid } from '@mantine/core';

// ❌ No longer works
function Demo() {
  return (
    <Grid gutter="xl">
      <Grid.Col span={6}>1</Grid.Col>
      <Grid.Col span={6}>2</Grid.Col>
    </Grid>
  );
}

// ✅ Use the gap prop
function Demo() {
  return (
    <Grid gap="xl">
      <Grid.Col span={6}>1</Grid.Col>
      <Grid.Col span={6}>2</Grid.Col>
    </Grid>
  );
}

// ✅ New: Separate row and column gaps
function Demo() {
  return (
    <Grid rowGap="xl" columnGap="sm">
      <Grid.Col span={6}>1</Grid.Col>
      <Grid.Col span={6}>2</Grid.Col>
    </Grid>
  );
}

Grid overflow="hidden" no longer required

The Grid component no longer uses negative margins for spacing between columns. It now uses native CSS gap property, so you can safely remove overflow="hidden" from your Grid components — it is no longer needed to prevent content overflow:

tsx

import { Grid } from '@mantine/core';

// ❌ overflow="hidden" is no longer needed
function Demo() {
  return (
    <Grid overflow="hidden">
      <Grid.Col span={6}>1</Grid.Col>
      <Grid.Col span={6}>2</Grid.Col>
    </Grid>
  );
}

// ✅ Remove overflow="hidden"
function Demo() {
  return (
    <Grid>
      <Grid.Col span={6}>1</Grid.Col>
      <Grid.Col span={6}>2</Grid.Col>
    </Grid>
  );
}

useLocalStorage and useSessionStorage return type

The useLocalStorage and useSessionStorage hooks now correctly include undefined in the return type when no defaultValue is provided. Previously, calling these hooks without defaultValue would type the value as T (e.g., string), even though at runtime the value could be undefined.

If you relied on the incorrect type, update your code to handle undefined:

tsx

import { useLocalStorage } from '@mantine/hooks';

// ❌ In 8.x, `value` was typed as `string` (incorrect)
const [value, setValue] = useLocalStorage({ key: 'my-key' });

// ✅ In 9.x, `value` is typed as `string | undefined`
const [value, setValue] = useLocalStorage({ key: 'my-key' });

// ✅ Provide defaultValue to keep the previous non-undefined type
const [value, setValue] = useLocalStorage({
  key: 'my-key',
  defaultValue: '',
});

The same change applies to readLocalStorageValue, useSessionStorage, and readSessionStorageValue.

Default border-radius change

In 8.x, the default border-radius (theme.defaultRadius) was sm (4px). In 9.x, the default border-radius was changed to md (8px). To keep the previous behavior, set defaultRadius to sm in the theme:

tsx

import { createTheme, MantineProvider } from '@mantine/core';

const theme = createTheme({
  defaultRadius: 'sm',
});

function Demo() {
  return <MantineProvider theme={theme}></MantineProvider>;
}

Notifications pauseResetOnHover default change

In 8.x, hovering over a notification paused the auto close timer only for that notification. In 9.x, the default behavior changed – hovering over any notification now pauses the auto close timer of all visible notifications. To keep the previous behavior, set pauseResetOnHover="notification":

tsx

import { Notifications } from '@mantine/notifications';

function Demo() {
  return <Notifications pauseResetOnHover="notification" />;
}

8.x → 9.x migration guide

8.x → 9.x migration guide

Migrate with LLM agents

Prerequisites

Update dependencies

use-form TransformValues type

Text color prop

Light variant color changes

Form resolvers

TypographyStylesProvider

Popover and Tooltip positionDependencies prop

use-fullscreen hook changes

use-mouse hook changes

use-mutation-observer hook changes

Rename hooks types

Collapse in -> expanded

Spoiler initialState -> defaultExpanded

Grid gutter -> gap

Grid overflow="hidden" no longer required

useLocalStorage and useSessionStorage return type

Default border-radius change

Notifications pauseResetOnHover default change