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Migration from v4 to v5

Yeah, v5 has been released!

If you're looking for the v4 docs, you can find the latest version here.

Introduction

This is a reference for upgrading your site from MUI Core v4 to v5. While there's a lot covered here, you probably won't need to do everything. We'll do our best to keep things easy to follow, and as sequential as possible, so you can quickly get rocking on v5!

Why you should migrate

To get the benefits of bug fixes and a lot of improvements such as the new styling engine. This documentation page covers the how of migrating from v4 to v5. The why is covered in the release blog post.

Migration steps

๐Ÿ’ก Prefer to create small commits on any changes to help the migration go smoother. If you encounter any issues, check the Troubleshooting section. For other errors not described there, create an issue with the following title format: [Migration] Summary of your issue.

Update React & TypeScript version

  • The minimum supported version of React was increased from v16.8.0 to v17.0.0.

  • The minimum supported version of TypeScript was increased from v3.2 to v3.5.

    We try to align with types released from DefinitelyTyped (i.e. packages published on npm under the @types namespace). We will not change the minimum supported version in a major version of MUI. However, we generally recommend not to use a TypeScript version older than the lowest supported version of DefinitelyTyped

Note: if your project includes these packages, please upgrade them to the latest version.

  • react-scripts
  • @types/react
  • @types/react-dom

๐Ÿ“ Please make sure that your application is still running without errors and commit the change before continuing the next step.

ThemeProvider setup

Make sure that ThemeProvider is defined at the root of your application (even if you are using the default theme) and NO useStyles is called before <ThemeProvider>. This is because we are going to use @mui/styles temporarily, which requires ThemeProvider.

import { ThemeProvider, createMuiTheme, makeStyles } from '@mui/material/styles';

const theme = createMuiTheme();

const useStyles = makeStyles((theme) => {
  root: {
    // some css that access to theme
  }
});

function App() {
  const classes = useStyles(); // โŒ If you have this, consider moving <ThemeProvider> to HOC and wrap the App
  return <ThemeProvider theme={theme}>{children}</ThemeProvider>;
}

๐Ÿ“ Please make sure that your application is still running without errors and commit the change before continuing the next step.

Update MUI version

To use the v5 version of MUI Core, you first need to update the package names:

@material-ui/core -> @mui/material
@material-ui/system -> @mui/system
@material-ui/unstyled -> @mui/core
@material-ui/styles -> @mui/styles
@material-ui/icons -> @mui/icons-material
@material-ui/lab -> @mui/lab
@material-ui/types -> @mui/types
@material-ui/styled-engine -> @mui/styled-engine
@material-ui/styled-engine-sc ->@mui/styled-engine-sc
@material-ui/private-theming -> @mui/private-theming
@material-ui/codemod -> @mui/codemod
@material-ui/docs -> @mui/docs
@material-ui/envinfo -> @mui/envinfo

The org & package names have been changed from @material-ui to @mui as part of the rebranding effort. For more details about it, check our blog post or #27803.

Then, you need to add the new peer dependencies - emotion packages:

npm install @emotion/react @emotion/styled

// or with `yarn`
yarn add @emotion/react @emotion/styled

๐Ÿ’ก If you want to use MUI Core v5 with styled-components instead of emotion, check out the installation guide.

If you are using @material-ui/pickers, it has moved to @mui/lab. You can follow these steps.

You should have installed @mui/styles now. It includes JSS, which duplicate with emotion. It's meant to allow a gradual migration to v5. You should be able to remove the dependency following these steps.

After the upgrade and migration of the packages, you can remove the old @material-ui/* packages by running yarn remove or npm uninstall.

Run codemods

We have prepared these codemods to ease your migration experience.

preset-safe

This codemod contains most of the transformers that are useful for migration. (This codemod should be applied only once per folder)

npx @mui/codemod v5.0.0/preset-safe <path>

If you want to run the transformers one by one, check out the preset-safe codemod for more details.

variant-prop

Transform <TextField/>, <FormControl/>, <Select/> component by applying variant="standard" if no variant is defined (because default variant has changed from standard in v4 to outlined in v5).

โ—๏ธ You should NOT use this codemod if you have already defined default variant: "outlined" in the theme.

// if you have theme setup like this, โŒ don't run this codemod.
// these default props can be removed later because `outlined` is the default value in v5
createMuiTheme({
  props: {
    MuiTextField: {
      variant: 'outlined',
    },
  },
});

However, if you want to keep variant="standard" to your components, run this codemod or configure theme default props.

npx @mui/codemod v5.0.0/variant-prop <path>

For more details, check out the variant-prop codemod.

Transform <Link/> component by apply underline="hover" if no underline prop defined (because default underline has changed from "hover" in v4 to "always" in v5).

โ—๏ธ You should NOT use this codemod if you have already defined default underline: "always" in the theme.

// if you have theme setup like this, โŒ don't run this codemod.
// this default props can be removed later because `always` is the default value in v5
createMuiTheme({
  props: {
    MuiLink: {
      underline: 'always',
    },
  },
});

However, if you want to keep variant="hover" to you components, run this codemod or configure theme default props.

npx @mui/codemod v5.0.0/link-underline-hover <path>

For more details, checkout link-underline-hover codemod.

Once you have completed the codemod step, try running your application again. At this point, it should be running without error. Otherwise check out the Troubleshooting section. Next step, handling breaking changes in each component.

Handling breaking changes

Supported browsers and node versions

The targets of the default bundle have changed. The exact versions will be pinned on release from the browserslist query "> 0.5%, last 2 versions, Firefox ESR, not dead, not IE 11, maintained node versions".

The default bundle supports the following minimum versions:

  • Node 12 (up from 8)
  • Chrome 90 (up from 49)
  • Edge 91 (up from 14)
  • Firefox 78 (up from 52)
  • Safari 14 (macOS) and 12.5 (iOS) (up from 10)
  • and more (see .browserslistrc (stable entry))

It no longer supports IE 11. If you need to support IE 11, check out our legacy bundle.

non-ref-forwarding class components

Support for non-ref-forwarding class components in the component prop or as immediate children has been dropped. If you were using unstable_createStrictModeTheme or didn't see any warnings related to findDOMNode in React.StrictMode then you don't need to do anything. Otherwise check out the Caveat with refs section in the composition guide to find out how to migrate. This change affects almost all components where you're using the component prop or passing children to components that require children to be elements (e.g. <MenuList><CustomMenuItem /></MenuList>)

Style library

The style library used by default in v5 is emotion. While migrating from JSS to emotion, and if you are using JSS style overrides for your components (for example overrides created by makeStyles), you will need to take care of the CSS injection order. To do so, you need to have the StyledEngineProvider with the injectFirst option at the top of your component tree.

โœ… This is handled in the preset-safe codemod.

Here is an example:

import * as React from 'react';
import { StyledEngineProvider } from '@mui/material/styles';

export default function GlobalCssPriority() {
  return (
    {/* Inject emotion before JSS */}
    <StyledEngineProvider injectFirst>
      {/* Your component tree. Now you can override MUI's styles. */}
    </StyledEngineProvider>
  );
}

Note: If you are using emotion to style your app, and have a custom cache, it will override the one provided by MUI. In order for the injection order to still be correct, you need to add the prepend option to createCache.

โœ… This is handled in the preset-safe codemod.

Here is an example:

 import * as React from 'react';
 import { CacheProvider } from '@emotion/react';
 import createCache from '@emotion/cache';

 const cache = createCache({
   key: 'css',
+  prepend: true,
 });

 export default function PlainCssPriority() {
   return (
     <CacheProvider value={cache}>
       {/* Your component tree. Now you can override MUI's styles. */}
     </CacheProvider>
   );
 }

Note: If you are using styled-components and have StyleSheetManager with a custom target, make sure that the target is the first element in the HTML <head>. To see how it can be done, take a look at the StyledEngineProvider implementation in the @mui/styled-engine-sc package.

Theme structure

The structure of the theme has changed in v5. You need to update its shape. For a smoother transition, the adaptV4Theme helper allows you to iteratively upgrade some of the theme changes to the new theme structure.

โœ… This is handled in the preset-safe codemod.

-import { createMuiTheme } from '@mui/material/styles';
+import { createTheme, adaptV4Theme } from '@mui/material/styles';

-const theme = createMuiTheme({
+const theme = createTheme(adaptV4Theme({
   // v4 theme
-});
+}));

โš ๏ธ This adapter only handles the input arguments of createTheme, if you modify the shape of the theme after its creation, you need to migrate the structure manually.

The following changes are supported by the adapter:

  • The "gutters" abstraction hasn't proven to be used frequently enough to be valuable.

    -theme.mixins.gutters(),
    +paddingLeft: theme.spacing(2),
    +paddingRight: theme.spacing(2),
    +[theme.breakpoints.up('sm')]: {
    +  paddingLeft: theme.spacing(3),
    +  paddingRight: theme.spacing(3),
    +},
    
  • theme.spacing now returns single values with px units by default. This change improves the integration with styled-components & emotion.

    โœ… This is handled in the preset-safe codemod by removing any 'px' suffix from theme.spacing calls in a template string.

    Before:

    theme.spacing(2) => 16
    

    After:

    theme.spacing(2) => '16px'
    
  • The theme.palette.type key was renamed to theme.palette.mode, to better follow the "dark mode" term that is usually used for describing this feature.

    โœ… This is handled in the preset-safe codemod.

     import { createTheme } from '@mui/material/styles';
    -const theme = createTheme({palette: { type: 'dark' }}),
    +const theme = createTheme({palette: { mode: 'dark' }}),
    
  • The default theme.palette.info colors were changed to pass AA standard contrast ratio in both light & dark mode.

     info = {
    -  main: cyan[500],
    +  main: lightBlue[700], // lightBlue[400] in "dark" mode
    
    -  light: cyan[300],
    +  light: lightBlue[500], // lightBlue[300] in "dark" mode
    
    -  dark: cyan[700],
    +  dark: lightBlue[900], // lightBlue[700] in "dark" mode
     }
    
  • The default theme.palette.success colors were changed to pass AA standard contrast ratio in both light & dark mode.

     success = {
    -  main: green[500],
    +  main: green[800], // green[400] in "dark" mode
    
    -  light: green[300],
    +  light: green[500], // green[300] in "dark" mode
    
    -  dark: green[700],
    +  dark: green[900], // green[700] in "dark" mode
     }
    
  • The default theme.palette.warning colors were changed to pass AA standard contrast ratio in both light & dark mode.

     warning = {
    -  main: orange[500],
    +  main: "#ED6C02", // orange[400] in "dark" mode
    
    -  light: orange[300],
    +  light: orange[500], // orange[300] in "dark" mode
    
    -  dark: orange[700],
    +  dark: orange[900], // orange[700] in "dark" mode
     }
    
  • The theme.palette.text.hint key was unused in MUI components, and has been removed. If you depend on it, you can add it back:

     import { createTheme } from '@mui/material/styles';
    
    -const theme = createTheme(),
    +const theme = createTheme({
    +  palette: { text: { hint: 'rgba(0, 0, 0, 0.38)' } },
    +});
    
  • The components' definitions in the theme were restructured under the components key, to allow for easier discoverability of the definitions related to any one component.

    1. props
     import { createTheme } from '@mui/material/styles';
    
     const theme = createTheme({
    -  props: {
    -    MuiButton: {
    -      disableRipple: true,
    -    },
    -  },
    +  components: {
    +    MuiButton: {
    +      defaultProps: {
    +        disableRipple: true,
    +      },
    +    },
    +  },
     });
    
    1. overrides
     import { createTheme } from '@mui/material/styles';
    
     const theme = createTheme({
    -  overrides: {
    -    MuiButton: {
    -      root: { padding: 0 },
    -    },
    -  },
    +  components: {
    +    MuiButton: {
    +      styleOverrides: {
    +        root: { padding: 0 },
    +      },
    +    },
    +  },
     });
    

Styles

  • Renamed fade to alpha to better describe its functionality. The previous name was leading to confusion when the input color already had an alpha value. The helper overrides the alpha value of the color.

    โœ… This is handled in the preset-safe codemod.

    - import { fade } from '@mui/material/styles';
    + import { alpha } from '@mui/material/styles';
    
    const classes = makeStyles(theme => ({
    -  backgroundColor: fade(theme.palette.primary.main, theme.palette.action.selectedOpacity),
    +  backgroundColor: alpha(theme.palette.primary.main, theme.palette.action.selectedOpacity),
    }));
    
  • The createStyles function from @mui/material/styles was moved to the one exported from @mui/styles. It is necessary for removing the dependency to @mui/styles in the core package.

    โœ… This is handled in the preset-safe codemod.

    -import { createStyles } from '@mui/material/styles';
    +import { createStyles } from '@mui/styles';
    

@mui/styles

ThemeProvider

If you are using the utilities from @mui/styles together with the @mui/material, you should replace the use of ThemeProvider from @mui/styles with the one exported from @mui/material/styles. This way, the theme provided in the context will be available in both the styling utilities exported from @mui/styles, like makeStyles, withStyles etc. and the MUI components.

-import { ThemeProvider } from '@mui/styles';
+import { ThemeProvider } from '@mui/material/styles';

Make sure to add a ThemeProvider at the root of your application, as the defaultTheme is no longer available.

Default theme (TypeScript)

The @mui/styles package is no longer part of @mui/material/styles. If you are using @mui/styles together with @mui/material you need to add a module augmentation for the DefaultTheme.

โœ… This is handled in the preset-safe codemod.

// in your theme file that you call `createTheme()`
import { Theme } from '@mui/material/styles';

declare module '@mui/styles' {
  interface DefaultTheme extends Theme {}
}

@mui/material/colors

  • Nested imports of more than 1 level are private. You can't import color from @mui/material/colors/red.

    โœ… This is handled in the preset-safe codemod.

    -import red from '@mui/material/colors/red';
    +import { red } from '@mui/material/colors';
    

@mui/material/styles

createGenerateClassName

  • The createGenerateClassName function is no longer exported from @mui/material/styles. You should import it directly from @mui/styles.

    โœ… This is handled in the preset-safe codemod.

    -import { createGenerateClassName } from '@mui/material/styles';
    +import { createGenerateClassName } from '@mui/styles';
    

createMuiTheme

  • The function createMuiTheme was renamed to createTheme to make it more intuitive to use with ThemeProvider.

    โœ… This is handled in the preset-safe codemod.

    -import { createMuiTheme } from '@mui/material/styles';
    +import { createTheme } from '@mui/material/styles';
    
    -const theme = createMuiTheme({
    +const theme = createTheme({
    

jssPreset

  • The jssPreset object is no longer exported from @mui/material/styles. You should import it directly from @mui/styles.

    โœ… This is handled in the preset-safe codemod.

    -import { jssPreset } from '@mui/material/styles';
    +import { jssPreset } from '@mui/styles';
    

makeStyles

  • The makeStyles JSS utility is no longer exported from @mui/material/styles. You can use @mui/styles/makeStyles instead. Make sure to add a ThemeProvider at the root of your application, as the defaultTheme is no longer available. If you are using this utility together with @mui/material, it's recommended that you use the ThemeProvider component from @mui/material/styles instead.

    โœ… This is handled in the preset-safe codemod.

    -import { makeStyles } from '@mui/material/styles';
    +import { makeStyles } from '@mui/styles';
    +import { createTheme, ThemeProvider } from '@mui/material/styles';
    
    +const theme = createTheme();
     const useStyles = makeStyles((theme) => ({
       background: theme.palette.primary.main,
     }));
     function Component() {
       const classes = useStyles();
       return <div className={classes.root} />
     }
    
     // In the root of your app
     function App(props) {
    -  return <Component />;
    +  return <ThemeProvider theme={theme}><Component {...props} /></ThemeProvider>;
     }
    

MuiThemeProvider

  • The MuiThemeProvider component is no longer exported from @mui/material/styles. Use ThemeProvider instead.

    โœ… This is handled in the preset-safe codemod.

    -import { MuiThemeProvider } from '@mui/material/styles';
    +import { ThemeProvider } from '@mui/material/styles';
    

ServerStyleSheets

  • The ServerStyleSheets component is no longer exported from @mui/material/styles. You should import it directly from @mui/styles.

    โœ… This is handled in the preset-safe codemod.

    -import { ServerStyleSheets } from '@mui/material/styles';
    +import { ServerStyleSheets } from '@mui/styles';
    

styled

  • The styled JSS utility is no longer exported from @mui/material/styles. You can use @mui/styles/styled instead. Make sure to add a ThemeProvider at the root of your application, as the defaultTheme is no longer available. If you are using this utility together with @mui/material, it's recommended you use the ThemeProvider component from @mui/material/styles instead.

    -import { styled } from '@mui/material/styles';
    +import { styled } from '@mui/styles';
    +import { createTheme, ThemeProvider } from '@mui/material/styles';
    
    +const theme = createTheme();
     const MyComponent = styled('div')(({ theme }) => ({ background: theme.palette.primary.main }));
    
     function App(props) {
    -  return <MyComponent />;
    +  return <ThemeProvider theme={theme}><MyComponent {...props} /></ThemeProvider>;
     }
    

StylesProvider

  • The StylesProvider component is no longer exported from @mui/material/styles. You should import it directly from @mui/styles.

    โœ… This is handled in the preset-safe codemod.

    -import { StylesProvider } from '@mui/material/styles';
    +import { StylesProvider } from '@mui/styles';
    

useThemeVariants

  • The useThemeVariants hook is no longer exported from @mui/material/styles. You should import it directly from @mui/styles.

    โœ… This is handled in the preset-safe codemod.

    -import { useThemeVariants } from '@mui/material/styles';
    +import { useThemeVariants } from '@mui/styles';
    

withStyles

  • Replace the innerRef prop with the ref prop. Refs are now automatically forwarded to the inner component.

    โœ… This is handled in the preset-safe codemod.

     import * as React from 'react';
     import { withStyles } from '@mui/styles';
    
     const MyComponent = withStyles({
       root: {
         backgroundColor: 'red',
       },
     })(({ classes }) => <div className={classes.root} />);
    
     function MyOtherComponent(props) {
       const ref = React.useRef();
    -  return <MyComponent innerRef={ref} />;
    +  return <MyComponent ref={ref} />;
     }
    
  • The withStyles JSS utility is no longer exported from @mui/material/styles. You can use @mui/styles/withStyles instead. Make sure to add a ThemeProvider at the root of your application, as the defaultTheme is no longer available. If you are using this utility together with @mui/material, you should use the ThemeProvider component from @mui/material/styles instead.

    โœ… This is handled in the preset-safe codemod.

    -import { withStyles } from '@mui/material/styles';
    +import { withStyles } from '@mui/styles';
    +import { createTheme, ThemeProvider } from '@mui/material/styles';
    
    +const defaultTheme = createTheme();
     const MyComponent = withStyles((props) => {
       const { classes, className, ...other } = props;
       return <div className={clsx(className, classes.root)} {...other} />
     })(({ theme }) => ({ root: { background: theme.palette.primary.main }}));
    
     function App() {
    -  return <MyComponent />;
    +  return <ThemeProvider theme={defaultTheme}><MyComponent /></ThemeProvider>;
     }
    

withTheme

  • The withTheme HOC utility has been removed from the @mui/material/styles package. You can use @mui/styles/withTheme instead. Make sure to add a ThemeProvider at the root of your application, as the defaultTheme is no longer available. If you are using this utility together with @mui/material, it's recommended you use the ThemeProvider component from @mui/material/styles instead.

    โœ… This is handled in the preset-safe codemod.

    -import { withTheme } from '@mui/material/styles';
    +import { withTheme } from '@mui/styles';
    +import { createTheme, ThemeProvider } from '@mui/material/styles';
    
    +const theme = createTheme();
     const MyComponent = withTheme(({ theme }) => <div>{props.theme.direction}</div>);
    
     function App(props) {
    -  return <MyComponent />;
    +  return <ThemeProvider theme={theme}><MyComponent {...props} /></ThemeProvider>;
     }
    
  • Replace the innerRef prop with the ref prop. Refs are now automatically forwarded to the inner component.

    import * as React from 'react';
    import { withTheme } from '@mui/styles';
    
    const MyComponent = withTheme(({ theme }) => <div>{props.theme.direction}</div>);
    
    function MyOtherComponent(props) {
      const ref = React.useRef();
    - return <MyComponent innerRef={ref} />;
    + return <MyComponent ref={ref} />;
    }
    

withWidth

  • This HOC was removed. There's an alternative using the useMediaQuery hook.

    โœ… This is handled in the preset-safe codemod by applying hard-coded function to prevent the application from crashing.

@material-ui/pickers

We have a dedicated page for migrating @material-ui/pickers to v5

System

  • The following system functions (and properties) were renamed because they are considered deprecated CSS:

    • gridGap to gap
    • gridRowGap to rowGap
    • gridColumnGap to columnGap

    โœ… This is handled in the preset-safe codemod.

  • Use spacing unit in gap, rowGap, and columnGap. If you were using a number previously, you need to mention the px to bypass the new transformation with theme.spacing.

    โœ… This is handled in the preset-safe codemod.

     <Box
    -  gap={2}
    +  gap="2px"
     >
    
  • Replace css prop with sx to avoid collision with styled-components & emotion css prop.

    โœ… This is handled in the preset-safe codemod.

    -<Box css={{ color: 'primary.main' }} />
    +<Box sx={{ color: 'primary.main' }} />
    

    Note that the system grid function wasn't documented in v4.

Core components

As the core components use emotion as their style engine, the props used by emotion are not intercepted. The prop as in the following code snippet will not be propagated to SomeOtherComponent.

<MuiComponent component={SomeOtherComponent} as="button" />

AppBar

  • Remove z-index when position static and relative. This avoids the creation of a stacking context and rendering issues.

  • The color prop has no longer any effect in dark mode. The app bar uses the background color required by the elevation to follow the Material Design guidelines. Use enableColorOnDark to restore the behavior of v4.

    <AppBar enableColorOnDark />
    

Alert

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import Alert from '@mui/lab/Alert';
    -import AlertTitle from '@mui/lab/AlertTitle';
    +import Alert from '@mui/material/Alert';
    +import AlertTitle from '@mui/material/AlertTitle';
    

Autocomplete

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import Autocomplete from '@mui/lab/Autocomplete';
    -import useAutocomplete  from '@mui/lab/useAutocomplete';
    +import Autocomplete from '@mui/material/Autocomplete';
    +import useAutoComplete from '@mui/material/useAutocomplete';
    
  • Remove debug prop. There are a couple of simpler alternatives: open={true}, Chrome devtools "Emulate focused", or React devtools prop setter.

  • renderOption should now return the full DOM structure of the option. It makes customizations easier. You can recover from the change with:

     <Autocomplete
    -  renderOption={(option, { selected }) => (
    -    <React.Fragment>
    +  renderOption={(props, option, { selected }) => (
    +    <li {...props}>
           <Checkbox
             icon={icon}
             checkedIcon={checkedIcon}
             style={{ marginRight: 8 }}
             checked={selected}
           />
           {option.title}
    -    </React.Fragment>
    +    </li>
       )}
     />
    
  • Rename closeIcon prop to clearIcon to avoid confusion.

    โœ… This is handled in the preset-safe codemod.

    -<Autocomplete closeIcon={defaultClearIcon} />
    +<Autocomplete clearIcon={defaultClearIcon} />
    
  • The following values of the reason argument in onChange and onClose were renamed for consistency:

    1. create-option to createOption
    2. select-option to selectOption
    3. remove-option to removeOption
  • Change the CSS rules that use [data-focus="true"] to use .Mui-focused. The data-focus attribute is not set on the focused option anymore, instead, global class names are used.

    -'.MuiAutocomplete-option[data-focus="true"]': {
    +'.MuiAutocomplete-option.Mui-focused': {
    
  • Rename getOptionSelected to isOptionEqualToValue to better describe its purpose.

    โœ… This is handled in the preset-safe codemod.

     <Autocomplete
    -  getOptionSelected={(option, value) => option.title === value.title}
    +  isOptionEqualToValue={(option, value) => option.title === value.title}
    

Avatar

  • Rename circle to circular for consistency:

    โœ… This is handled in the preset-safe codemod.

    -<Avatar variant="circle">
    -<Avatar classes={{ circle: 'className' }}>
    +<Avatar variant="circular">
    +<Avatar classes={{ circular: 'className' }}>
    

    Since circular is the default value, the variant prop can be deleted:

    -<Avatar variant="circle">
    +<Avatar>
    
  • Move the AvatarGroup from the lab to the core.

    โœ… This is handled in the preset-safe codemod.

    -import AvatarGroup from '@mui/lab/AvatarGroup';
    +import AvatarGroup from '@mui/material/AvatarGroup';
    

Badge

  • Rename circle to circular and rectangle to rectangular for consistency.

    โœ… This is handled in the preset-safe codemod.

    -<Badge overlap="circle">
    -<Badge overlap="rectangle">
    +<Badge overlap="circular">
    +<Badge overlap="rectangular">
    
     <Badge classes={{
    -  anchorOriginTopRightRectangle: 'className',
    -  anchorOriginBottomRightRectangle: 'className',
    -  anchorOriginTopLeftRectangle: 'className',
    -  anchorOriginBottomLeftRectangle: 'className',
    -  anchorOriginTopRightCircle: 'className',
    -  anchorOriginBottomRightCircle: 'className',
    -  anchorOriginTopLeftCircle: 'className',
    +  anchorOriginTopRightRectangular: 'className',
    +  anchorOriginBottomRightRectangular: 'className',
    +  anchorOriginTopLeftRectangular: 'className',
    +  anchorOriginBottomLeftRectangular: 'className',
    +  anchorOriginTopRightCircular: 'className',
    +  anchorOriginBottomRightCircular: 'className',
    +  anchorOriginTopLeftCircular: 'className',
     }}>
    

BottomNavigation

  • TypeScript: The event in onChange is no longer typed as a React.ChangeEvent but React.SyntheticEvent.

    -<BottomNavigation onChange={(event: React.ChangeEvent<{}>) => {}} />
    +<BottomNavigation onChange={(event: React.SyntheticEvent) => {}} />
    

BottomNavigationAction

  • Remove the span element that wraps the children. Remove the wrapper classKey too. More details about this change.

     <button class="MuiBottomNavigationAction-root">
    -  <span class="MuiBottomNavigationAction-wrapper">
         {icon}
         <span class="MuiBottomNavigationAction-label">
           {label}
         </span>
    -  </span>
     </button>
    

Box

  • The borderRadius system prop value transformation has been changed. If it receives a number, it multiplies this value with the theme.shape.borderRadius value. Use a string to provide an explicit px value.

    โœ… This is handled in the preset-safe codemod.

    -<Box borderRadius="borderRadius">
    +<Box borderRadius={1}>
    
    -<Box borderRadius={16}>
    +<Box borderRadius="16px">
    
  • The Box system props have an optional alternative API in v5, using the sx prop. You can read this section for the "why" behind this new API.

    โœ… This is handled in the preset-safe codemod.

    <Box border="1px dashed grey" p={[2, 3, 4]} m={2}>
    <Box sx={{ border: "1px dashed grey", p: [2, 3, 4], m: 2 }}>
    
  • The following properties have been renamed because they are considered deprecated CSS properties by the CSS specification:

    โœ… This is handled in the preset-safe codemod.

    1. gridGap to gap
    2. gridColumnGap to columnGap
    3. gridRowGap to rowGap
    -<Box gridGap={1}>
    -<Box gridColumnGap={2}>
    -<Box gridRowGap={3}>
    +<Box gap={1}>
    +<Box columnGap={2}>
    +<Box rowGap={3}>
    

    (Note that the system grid function wasn't documented in v4.)

  • The clone prop was removed because its behavior can be obtained by applying the sx prop directly to the child if it is a MUI component.

    -<Box sx={{ border: '1px dashed grey' }} clone>
    -  <Button>Save</Button>
    -</Box>
    +<Button sx={{ border: '1px dashed grey' }}>Save</Button>
    
  • The ability to pass a render prop was removed because its behavior can be obtained by applying the sx prop directly to the child if it is a MUI component.

    -<Box sx={{ border: '1px dashed grey' }}>
    -  {(props) => <Button {...props}>Save</Button>}
    -</Box>
    +<Button sx={{ border: '1px dashed grey' }}>Save</Button>
    

    For non-MUI components, use the component prop.

    -<Box sx={{ border: '1px dashed grey' }}>
    -  {(props) => <button {...props}>Save</button>}
    -</Box>
    +<Box component="button" sx={{ border: '1px dashed grey' }}>Save</Box>
    

Button

  • The button color prop is now "primary" by default, and "default" has been removed. This makes the button closer to the Material Design guidelines and simplifies the API.

    โœ… This is handled in the preset-safe codemod.

    -<Button color="default">
    +<Button>
    
  • span element that wraps children has been removed. label classKey is also removed. More details about this change.

     <button class="MuiButton-root">
    -  <span class="MuiButton-label">
         children
    -  </span>
     </button>
    

Chip

  • Rename default variant to filled for consistency.

    โœ… This is handled in the preset-safe codemod.

    Since filled is the default value, the variant prop can be deleted:

    -<Chip variant="default">
    +<Chip>
    

Checkbox

  • The component doesn't have .MuiIconButton-root and .MuiIconButton-label class names anymore, target .MuiButtonBase-root instead.

    - <span class="MuiIconButton-root MuiButtonBase-root MuiCheckbox-root PrivateSwitchBase-root">
    -   <span class="MuiIconButton-label">
    -     <input class="PrivateSwitchBase-input">
    + <span class="MuiButtonBase-root MuiCheckbox-root PrivateSwitchBase-root">
    +   <span class="PrivateSwitchBase-input">
    

CircularProgress

  • The static variant has been renamed to determinate, and the previous appearance of determinate has been replaced by that of static. It was an exception to Material Design, and was removed from the specification.

    โœ… This is handled in the preset-safe codemod.

    -<CircularProgress variant="static" classes={{ static: 'className' }} />
    +<CircularProgress variant="determinate" classes={{ determinate: 'className' }} />
    

NB: If you had previously customized determinate, your customizations are probably no longer valid. Please remove them.

Collapse

  • The collapsedHeight prop was renamed collapsedSize to support the horizontal direction.

    โœ… This is handled in the preset-safe codemod.

    -<Collapse collapsedHeight={40}>
    +<Collapse collapsedSize={40}>
    
  • The classes.container key was changed to match the convention of the other components.

    -<Collapse classes={{ container: 'collapse' }}>
    +<Collapse classes={{ root: 'collapse' }}>
    

CssBaseline

  • The component was migrated to use the @mui/styled-engine (emotion or styled-components) instead of jss. You should remove the @global key when defining the style overrides for it. You could also start using the CSS template syntax over the JavaScript object syntax.

    const theme = createTheme({
      components: {
        MuiCssBaseline: {
    -     styleOverrides: {
    -       '@global': {
    -         html: {
    -           WebkitFontSmoothing: 'auto',
    -         },
    -       },
    -     },
    +     styleOverrides: `
    +       html {
    +         -webkit-font-smoothing: auto;
    +       }
    +     `
        },
      },
    });
    
  • The body font size has changed from theme.typography.body2 (0.875rem) to theme.typography.body1 (1rem). To return to the previous size, you can override it in the theme:

    const theme = createTheme({
      typography: {
        body1: {
          fontSize: '0.875rem',
        },
      },
    });
    

    (Note that this will also affect use of the Typography component with the default body1 variant).

Dialog

  • The onE* transition props were removed. Use TransitionProps instead.

    โœ… This is handled in the preset-safe codemod.

     <Dialog
    -  onEnter={onEnter}
    -  onEntered={onEntered}
    -  onEntering={onEntering}
    -  onExit={onExit}
    -  onExited={onExited}
    -  onExiting={onExiting}
    +  TransitionProps={{
    +    onEnter,
    +    onEntered,
    +    onEntering,
    +    onExit,
    +    onExited,
    +    onExiting,
    +  }}
     >
    
  • Remove the disableBackdropClick prop because it is redundant. Ignore close events from onClose when reason === 'backdropClick' instead.

    โœ… This is handled in the preset-safe codemod.

     <Dialog
    -  disableBackdropClick
    -  onClose={handleClose}
    +  onClose={(event, reason) => {
    +    if (reason !== 'backdropClick') {
    +      handleClose(event, reason);
    +    }
    +  }}
     />
    
  • Remove the withMobileDialog higher-order component. The hook API allows a simpler and more flexible solution:

    โœ… This is handled in the preset-safe codemod by applying hard-coded function to prevent application crash, further fixes are required.

    -import withMobileDialog from '@mui/material/withMobileDialog';
    +import { useTheme, useMediaQuery } from '@mui/material';
    
    function ResponsiveDialog(props) {
    - const { fullScreen } = props;
    + const theme = useTheme();
    + const fullScreen = useMediaQuery(theme.breakpoints.down('sm'));
      const [open, setOpen] = React.useState(false);
    
    // ...
    
    -export default withMobileDialog()(ResponsiveDialog);
    +export default ResponsiveDialog;
    
  • Flatten DialogTitle DOM structure, remove disableTypography prop

    โœ… This is handled in the preset-safe codemod.

    -<DialogTitle disableTypography>
    -  <Typography variant="h4" component="h2">
    +<DialogTitle>
    +  <Typography variant="h4" component="span">
         My header
       </Typography>
    

Divider

  • Use border instead of background color. It prevents inconsistent height on scaled screens. If you have customized the color of the border, you will need to update the CSS property override:

    .MuiDivider-root {
    - background-color: #f00;
    + border-color: #f00;
    }
    

ExpansionPanel

  • Rename the ExpansionPanel components to Accordion to use a more common naming convention:

    โœ… This is handled in the preset-safe codemod.

    -import ExpansionPanel from '@mui/material/ExpansionPanel';
    -import ExpansionPanelSummary from '@mui/material/ExpansionPanelSummary';
    -import ExpansionPanelDetails from '@mui/material/ExpansionPanelDetails';
    -import ExpansionPanelActions from '@mui/material/ExpansionPanelActions';
    +import Accordion from '@mui/material/Accordion';
    +import AccordionSummary from '@mui/material/AccordionSummary';
    +import AccordionDetails from '@mui/material/AccordionDetails';
    +import AccordionActions from '@mui/material/AccordionActions';
    
    -<ExpansionPanel>
    +<Accordion>
    -  <ExpansionPanelSummary>
    +  <AccordionSummary>
         <Typography>Location</Typography>
         <Typography>Select trip destination</Typography>
    -  </ExpansionPanelSummary>
    +  </AccordionSummary>
    -  <ExpansionPanelDetails>
    +  <AccordionDetails>
         <Chip label="Barbados" onDelete={() => {}} />
         <Typography variant="caption">Select your destination of choice</Typography>
    -  </ExpansionPanelDetails>
    +  </AccordionDetails>
       <Divider />
    -  <ExpansionPanelActions>
    +  <AccordionActions>
         <Button size="small">Cancel</Button>
         <Button size="small">Save</Button>
    -  </ExpansionPanelActions>
    +  </AccordionActions>
    -</ExpansionPanel>
    +</Accordion>
    
  • TypeScript: The event in onChange is no longer typed as a React.ChangeEvent but React.SyntheticEvent.

    -<Accordion onChange={(event: React.ChangeEvent<{}>, expanded: boolean) => {}} />
    +<Accordion onChange={(event: React.SyntheticEvent, expanded: boolean) => {}} />
    

ExpansionPanelDetails

  • Remove display: flex from AccordionDetails (formerly ExpansionPanelDetails) as its too opinionated. Most developers expect a display block.

ExpansionPanelSummary

  • Rename focused to focusVisible for consistency:

     <AccordionSummary
       classes={{
    -    focused: 'custom-focus-visible-classname',
    +    focusVisible: 'custom-focus-visible-classname',
       }}
      />
    
  • Remove IconButtonProps prop from AccordionSummary (formerly ExpansionPanelSummary). The component renders a <div> element instead of an IconButton. The prop is no longer necessary.

Fab

  • Rename round to circular for consistency:

    โœ… This is handled in the preset-safe codemod.

    -<Fab variant="round">
    +<Fab variant="circular">
    
  • span element that wraps children has been removed. label classKey is also removed. More details about this change.

     <button class="MuiFab-root">
    -  <span class="MuiFab-label">
         {children}
    -  </span>
     </button>
    

FormControl

  • Change the default variant from standard to outlined. Standard has been removed from the Material Design guidelines.

    โœ… This is handled in variant-prop codemod, read the details before running this codemod.

    -<FormControl value="Standard" />
    -<FormControl value="Outlined" variant="outlined" />
    +<FormControl value="Standard" variant="standard" />
    +<FormControl value="Outlined" />
    

FormControlLabel

  • The label prop is now required. If you were using a FormControlLabel without a label, you can replace it with just the value of the control prop.
-<FormControlLabel control={<Checkbox />} />
+<Checkbox />

Grid

  • Rename justify prop to justifyContent to align with the CSS property name.

    โœ… This is handled in the preset-safe codemod.

    -<Grid justify="center">
    +<Grid justifyContent="center">
    
  • The props: alignItems alignContent and justifyContent and their classes and style overrides keys were removed: "align-items-xs-center", "align-items-xs-flex-start", "align-items-xs-flex-end", "align-items-xs-baseline", "align-content-xs-center", "align-content-xs-flex-start", "align-content-xs-flex-end", "align-content-xs-space-between", "align-content-xs-space-around", "justify-content-xs-center", "justify-content-xs-flex-end", "justify-content-xs-space-between", "justify-content-xs-space-around" and "justify-content-xs-space-evenly". These props are now considered part of the system, not on the Grid component itself. If you still wish to add overrides for them, you can use the theme.components.MuiGrid.variants options.

    โœ… This is handled in the preset-safe codemod.

    const theme = createTheme({
      components: {
        MuiGrid: {
    -     styleOverrides: {
    -       "align-items-xs-flex-end": {
    -         marginTop: '20px',
    -       },
    -     },
    +     variants: {
    +       props: { alignItems: "flex-end" },
    +       style: {
    +         marginTop: '20px',
    +       },
    +     }],
        },
      },
    });
    

GridList

  • Rename the GridList components to ImageList to align with the current Material Design naming.

    โœ… This is handled in the preset-safe codemod.

  • Rename the GridList spacing prop to gap to align with the CSS attribute.

  • Rename the GridList cellHeight prop to rowHeight.

  • Add the variant prop to GridList.

  • Rename the GridListItemBar actionPosition prop to position. (Note also the related classname changes.)

  • Use CSS object-fit. For IE11 support either use a polyfill such as https://www.npmjs.com/package/object-fit-images, or continue to use the v4 component.

    -import GridList from '@mui/material/GridList';
    -import GridListTile from '@mui/material/GridListTile';
    -import GridListTileBar from '@mui/material/GridListTileBar';
    +import ImageList from '@mui/material/ImageList';
    +import ImageListItem from '@mui/material/ImageListItem';
    +import ImageListItemBar from '@mui/material/ImageListItemBar';
    
    -<GridList spacing={8} cellHeight={200}>
    -  <GridListTile>
    +<ImageList gap={8} rowHeight={200}>
    +  <ImageListItem>
        <img src="file.jpg" alt="Image title" />
    -    <GridListTileBar
    +    <ImageListItemBar
          title="Title"
          subtitle="Subtitle"
        />
    -  </GridListTile>
    -</GridList>
    +  </ImageListItem>
    +</ImageList>
    

Hidden

  • This component is deprecated because its functionality can be created with the sx prop or the useMediaQuery hook.

    โœ… This is handled in the preset-safe codemod by applying fake Hidden component to prevent application crash, further fixes are required.

    Use the sx prop to replace implementation="css":

    -<Hidden implementation="css" xlUp><Paper /></Hidden>
    -<Hidden implementation="css" xlUp><button /></Hidden>
    +<Paper sx={{ display: { xl: 'none', xs: 'block' } }} />
    +<Box component="button" sx={{ display: { xl: 'none', xs: 'block' } }} />
    
    -<Hidden implementation="css" mdDown><Paper /></Hidden>
    -<Hidden implementation="css" mdDown><button /></Hidden>
    +<Paper sx={{ display: { xs: 'none', md: 'block' } }} />
    +<Box component="button" sx={{ display: { xs: 'none', md: 'block' } }} />
    

    Use the useMediaQuery hook to replace implementation="js":

    -<Hidden implementation="js" xlUp><Paper /></Hidden>
    +const hidden = useMediaQuery(theme => theme.breakpoints.up('xl'));
    +return hidden ? null : <Paper />;
    

Icon

  • The default value of fontSize was changed from default to medium for consistency. In the unlikely event that you were using the value default, the prop can be removed:

    -<Icon fontSize="default">icon-name</Icon>
    +<Icon>icon-name</Icon>
    

IconButton

  • The default size's padding is reduced to 8px which makes the default IconButton size of 40px. To get the old default size (48px), use size="large". The change was done to better match Google's products when Material Design stopped documenting the icon button pattern.

    โœ… This is handled in the preset-safe codemod.

    - <IconButton>
    + <IconButton size="large">
    
  • span element that wraps children has been removed. label classKey is also removed. More details about this change.

     <button class="MuiIconButton-root">
    -  <span class="MuiIconButton-label">
         <svg />
    -  </span>
     </button>
    
  • The default underline prop is changed from "hover" to "always". To get the same behavior as in v4, apply defaultProps in theme

    โœ… This is handled in link-underline-hover codemod, read the details before running this codemod.

    createTheme({
      components: {
        MuiLink: {
          defaultProps: {
            underline: 'hover',
          },
        },
      },
    });
    

Menu

  • The onE* transition props were removed. Use TransitionProps instead.

    โœ… This is handled in the preset-safe codemod.

     <Menu
    -  onEnter={onEnter}
    -  onEntered={onEntered}
    -  onEntering={onEntering}
    -  onExit={onExit}
    -  onExited={onExited}
    -  onExiting={onExiting}
    +  TransitionProps={{
    +    onEnter,
    +    onEntered,
    +    onEntering,
    +    onExit,
    +    onExited,
    +    onExiting,
    +  }}
     >
    

    Note: The selectedMenu variant will no longer vertically align the selected item with the anchor.

  • Change the default value of anchorOrigin.vertical to follow the Material Design guidelines. The menu now displays below the anchor instead of on top of it. You can restore the previous behavior with:

     <Menu
    +  anchorOrigin={{
    +    vertical: 'top',
    +    horizontal: 'left',
    +  }}
    

MenuItem

  • The MenuItem component inherits the ButtonBase component instead of ListItem. The class names related to "MuiListItem-*" are removed and theming ListItem is no longer affecting MenuItem.

    -<li className="MuiButtonBase-root MuiMenuItem-root MuiListItem-root">
    +<li className="MuiButtonBase-root MuiMenuItem-root">
    
  • prop listItemClasses is removed, use classes instead.

    -<MenuItem listItemClasses={{...}}>
    +<MenuItem classes={{...}}>
    

    Read more about MenuItem CSS API

Modal

  • Remove the disableBackdropClick prop because it is redundant. Use onClose with reason === 'backdropClick' instead.

    โœ… This is handled in the preset-safe codemod.

     <Modal
    -  disableBackdropClick
    -  onClose={handleClose}
    +  onClose={(event, reason) => {
    +    if (reason !== 'backdropClick') {
    +      handleClose(event, reason);
    +    }
    +  }}
     />
    
  • Remove the onEscapeKeyDown prop because it is redundant. Use onClose with reason === "escapeKeyDown" instead.

    โœ… This is handled in the preset-safe codemod.

     <Modal
    -  onEscapeKeyDown={handleEscapeKeyDown}
    +  onClose={(event, reason) => {
    +    if (reason === 'escapeKeyDown') {
    +      handleEscapeKeyDown(event);
    +    }
    +  }}
     />
    
  • Remove onRendered prop. Depending on your use case either use a callback ref on the child element or an effect hook in the child component.

NativeSelect

  • Merge the selectMenu slot into select. Slot selectMenu was redundant. The root slot is no longer applied to the select, but to the root.

    -<NativeSelect classes={{ root: 'class1', select: 'class2', selectMenu: 'class3' }} />
    +<NativeSelect classes={{ select: 'class1 class2 class3' }} />
    

OutlinedInput

  • Remove the labelWidth prop. The label prop now fulfills the same purpose, using CSS layout instead of JavaScript measurement to render the gap in the outlined.

    -<OutlinedInput labelWidth={20} />
    +<OutlinedInput label="First Name" />
    

Paper

  • Change the background opacity based on the elevation in dark mode. This change was done to follow the Material Design guidelines. You can revert it in the theme:

    const theme = createTheme({
      components: {
        MuiPaper: {
    +     styleOverrides: { root: { backgroundImage: 'unset' } },
        },
      },
    });
    

Pagination

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import Pagination from '@mui/lab/Pagination';
    -import PaginationItem from '@mui/lab/PaginationItem';
    -import { usePagination } from '@mui/lab/Pagination';
    +import Pagination from '@mui/material/Pagination';
    +import PaginationItem from '@mui/material/PaginationItem';
    +import usePagination from '@mui/material/usePagination';
    
  • Rename round to circular for consistency:

    โœ… This is handled in the preset-safe codemod.

    -<Pagination shape="round">
    -<PaginationItem shape="round">
    +<Pagination shape="circular">
    +<PaginationItem shape="circular">
    

Popover

  • The onE* transition props were removed. Use TransitionProps instead.

    โœ… This is handled in the preset-safe codemod.

     <Popover
    -  onEnter={onEnter}
    -  onEntered={onEntered}
    -  onEntering={onEntering}
    -  onExit={onExit}
    -  onExited={onExited}
    -  onExiting={onExiting}
    +  TransitionProps={{
    +    onEnter,
    +    onEntered,
    +    onEntering,
    +    onExit,
    +    onExited,
    +    onExiting,
    +  }}
     >
    
  • The getContentAnchorEl prop was removed to simplify the positioning logic.

Popper

  • Upgrade Popper.js from v1 to v2. This third-party library has introduced a lot of changes.
    You can read their migration guide or the following summary:

    • The CSS prefixes have changed:

      popper: {
        zIndex: 1,
      - '&[x-placement*="bottom"] .arrow': {
      + '&[data-popper-placement*="bottom"] .arrow': {
      
    • Method names have changed:

      -popperRef.current.scheduleUpdate()
      +popperRef.current.update()
      
      -popperRef.current.update()
      +popperRef.current.forceUpdate()
      
    • Modifiers' API has changed a lot. There are too many changes to be covered here.

Portal

  • Remove onRendered prop. Depending on your use case either use a callback ref on the child element or an effect hook in the child component.

Radio

  • The radio color prop is now "primary" by default. To continue using the "secondary" color, you must explicitly indicate secondary. This brings the radio closer to the Material Design guidelines.

    -<Radio />
    +<Radio color="secondary />
    
  • The component doesn't have .MuiIconButton-root and .MuiIconButton-label class names anymore, target .MuiButtonBase-root instead.

    - <span class="MuiIconButton-root MuiButtonBase-root MuiRadio-root PrivateSwitchBase-root">
    -   <span class="MuiIconButton-label">
    -     <input class="PrivateSwitchBase-input">
    + <span class="MuiButtonBase-root MuiRadio-root PrivateSwitchBase-root">
    +   <span class="PrivateSwitchBase-input">
    

Rating

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import Rating from '@mui/lab/Rating';
    +import Rating from '@mui/material/Rating';
    
  • Change the default empty icon to improve accessibility. If you have a custom icon prop but no emptyIcon prop, you can restore the previous behavior with:

     <Rating
       icon={customIcon}
    +  emptyIcon={null}
     />
    
  • Rename visuallyhidden to visuallyHidden for consistency:

     <Rating
       classes={{
    -    visuallyhidden: 'custom-visually-hidden-classname',
    +    visuallyHidden: 'custom-visually-hidden-classname',
       }}
     />
    

RootRef

  • This component was removed. You can get a reference to the underlying DOM node of our components via ref prop. The component relied on ReactDOM.findDOMNode which is deprecated in React.StrictMode.

    โœ… This is handled in the preset-safe codemod by applying fake RootRef component to prevent application crash, further fixes are required.

    -<RootRef rootRef={ref}>
    -  <Button />
    -</RootRef>
    +<Button ref={ref} />
    

Select

  • Change the default variant from standard to outlined. Standard has been removed from the Material Design guidelines. If you are composing the Select with a form control component, you only need to update FormControl, the select inherits the variant from its context.

    โœ… This is handled in variant-prop codemod, read the details before running this codemod.

    -<Select value="Standard" />
    -<Select value="Outlined" variant="outlined" />
    +<Select value="Standard" variant="standard" />
    +<Select value="Outlined" />
    
  • Remove the labelWidth prop. The label prop now fulfills the same purpose, using CSS layout instead of JavaScript measurement to render the gap in the outlined. The TextField already handles it by default.

    -<Select variant="outlined" labelWidth={20} />
    +<Select variant="outlined" label="Gender" />
    
  • Merge the selectMenu slot into select. Slot selectMenu was redundant. The root slot is no longer applied to the select, but to the root.

    -<Select classes={{ root: 'class1', select: 'class2', selectMenu: 'class3' }} />
    +<Select classes={{ select: 'class1 class2 class3' }} />
    
  • The event in onChange is now a synthetic, native Event not a React event.

    -<Select onChange={(event: React.SyntheticEvent, value: unknown) => {}} />
    +<Select onChange={(event: Event, value: unknown) => {}} />
    

    This was necessary to prevent overriding of event.target of the events that caused the change.

Skeleton

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import Skeleton from '@mui/lab/Skeleton';
    +import Skeleton from '@mui/material/Skeleton';
    
  • Rename circle to circular and rect to rectangular for consistency:

    โœ… This is handled in the preset-safe codemod.

    -<Skeleton variant="circle" />
    -<Skeleton variant="rect" />
    -<Skeleton classes={{ circle: 'custom-circle-classname', rect: 'custom-rect-classname',  }} />
    +<Skeleton variant="circular" />
    +<Skeleton variant="rectangular" />
    +<Skeleton classes={{ circular: 'custom-circle-classname', rectangular: 'custom-rect-classname',  }} />
    

Slider

  • The event in onChange is now a synthetic, native Event, not a React event.

    -<Slider onChange={(event: React.SyntheticEvent, value: unknown) => {}} />
    +<Slider onChange={(event: Event, value: unknown) => {}} />
    

    This was necessary to prevent overriding of event.target of the events that caused the change.

  • The ValueLabelComponent and ThumbComponent prop is now part of the components prop.

     <Slider
    -  ValueLabelComponent={CustomValueLabel}
    -  ThumbComponent={CustomThumb}
    +  components={{
    +    ValueLabel: CustomValueLabel,
    +    Thumb: CustomThumb,
    +  }}
     />
    
  • Rework the CSS to match the latest Material Design guidelines and make custom styles more intuitive. See documentation.

    You can reduce the density of the slider, closer to v4 with the size="small" prop.

Snackbar

  • The notification now displays at the bottom left on large screens. This better matches the behavior of Gmail, Google Keep, material.io, etc. You can restore the previous behavior with:

    -<Snackbar />
    +<Snackbar anchorOrigin={{ vertical: 'bottom', horizontal: 'center' }} />
    
  • The onE* transition props were removed. Use TransitionProps instead.

    โœ… This is handled in the preset-safe codemod.

     <Snackbar
    -  onEnter={onEnter}
    -  onEntered={onEntered}
    -  onEntering={onEntering}
    -  onExit={onExit}
    -  onExited={onExited}
    -  onExiting={onExiting}
    +  TransitionProps={{
    +    onEnter,
    +    onEntered,
    +    onEntering,
    +    onExit,
    +    onExited,
    +    onExiting,
    +  }}
     >
    

SpeedDial

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import SpeedDial from '@mui/lab/SpeedDial';
    -import SpeedDialAction from '@mui/lab/SpeedDialAction';
    -import SpeedDialIcon from '@mui/lab/SpeedDialIcon';
    +import SpeedDial from '@mui/material/SpeedDial';
    +import SpeedDialAction from '@mui/material/SpeedDialAction';
    +import SpeedDialIcon from '@mui/material/SpeedDialIcon';
    

Stepper

  • The root component (Paper) was replaced with a div. Stepper no longer has elevation, nor inherits Paper's props. This change is meant to encourage composition.

    +<Paper square elevation={2}>
    -  <Stepper elevation={2}>
    +  <Stepper>
         <Step>
           <StepLabel>Hello world</StepLabel>
         </Step>
       </Stepper>
    +<Paper>
    
  • Remove the built-in 24px padding.

    -<Stepper>
    +<Stepper style={{ padding: 24 }}>
       <Step>
         <StepLabel>Hello world</StepLabel>
       </Step>
     </Stepper>
    

SvgIcon

  • The default value of fontSize was changed from default to medium for consistency. In the unlikey event that you were using the value default, the prop can be removed:

    -<SvgIcon fontSize="default">
    +<SvgIcon>
       <path d="M10 20v-6h4v6h5v-8h3L12 3 2 12h3v8z" />
     </SvgIcon>
    

Switch

  • Deprecate the second argument from onChange. You can pull out the checked state by accessing event.target.checked.

    function MySwitch() {
    - const handleChange = (event: React.ChangeEvent<HTMLInputElement>, checked: boolean) => {
    + const handleChange = (event: React.ChangeEvent<HTMLInputElement>) => {
    +   const checked = event.target.checked;
      };
    
      return <Switch onChange={handleChange} />;
    }
    
  • The switch color prop is now "primary" by default. To continue using the "secondary" color, you must explicitly indicate secondary. This brings the switch closer to the Material Design guidelines.

    -<Switch />
    +<Switch color="secondary" />
    
  • The component doesn't have .MuiIconButton-root and .MuiIconButton-label class names anymore, target .MuiButtonBase-root instead.

     <span class="MuiSwitch-root">
    -  <span class="MuiIconButton-root MuiButtonBase-root MuiSwitch-switchBase PrivateSwitchBase-root">
    -    <span class="MuiIconButton-label">
    -      <input class="MuiSwitch-input PrivateSwitchBase-input">
    +  <span class="MuiButtonBase-root MuiSwitch-switchBase PrivateSwitchBase-root">
    +    <span class="MuiSwitch-input PrivateSwitchBase-input">
    

Table

  • Rename the default value of the padding prop to normal.

    -<Table padding="default" />
    -<TableCell padding="default" />
    +<Table padding="normal" />
    +<TableCell padding="normal" />
    

TablePagination

  • The customization of the table pagination's actions labels must be done with the getItemAriaLabel prop. This increases consistency with the Pagination component.

     <TablePagination
    -  backIconButtonText="Avant"
    -  nextIconButtonText="Aprรจs"
    +  getItemAriaLabel={โ€ฆ}
    
  • Rename onChangeRowsPerPage to onRowsPerPageChange and onChangePage to onPageChange due to API consistency.

    โœ… This is handled in the preset-safe codemod.

     <TablePagination
    -  onChangeRowsPerPage={()=>{}}
    -  onChangePage={()=>{}}
    +  onRowsPerPageChange={()=>{}}
    +  onPageChange={()=>{}}
    
  • Separate classes for different table pagination labels. This allows simpler customizations.

     <TablePagination
    -  classes={{ caption: 'foo' }}
    +  classes={{ selectLabel: 'foo', displayedRows: 'foo' }}
     />
    
  • Move the custom class on input to select. The input key is being applied on another element.

     <TablePagination
    -  classes={{ input: 'foo' }}
    +  classes={{ select: 'foo' }}
     />
    

Tabs

  • Change the default indicatorColor and textColor prop values to "primary". This is done to match the most common use cases with Material Design.

    -<Tabs />
    +<Tabs indicatorColor="primary" textColor="inherit" />
    
  • TypeScript: The event in onChange is no longer typed as a React.ChangeEvent but React.SyntheticEvent.

    -<Tabs onChange={(event: React.ChangeEvent<{}>, value: unknown) => {}} />
    +<Tabs onChange={(event: React.SyntheticEvent, value: unknown) => {}} />
    
  • The API that controls the scroll buttons has been split it in two props.

    • The scrollButtons prop controls when the scroll buttons are displayed depending on the space available.
    • The allowScrollButtonsMobile prop removes the CSS media query that systematically hide the scroll buttons on mobile.

    โœ… This is handled in the preset-safe codemod.

    -<Tabs scrollButtons="on" />
    -<Tabs scrollButtons="desktop" />
    -<Tabs scrollButtons="off" />
    +<Tabs scrollButtons allowScrollButtonsMobile />
    +<Tabs scrollButtons />
    +<Tabs scrollButtons={false} />
    

Tab

  • Tab minWidth changed from 72px => 90px (without media-query) according to material-design spec

  • Tab maxWidth changed from 264px => 360px according to material-design spec

  • span element that wraps children has been removed. wrapper classKey is also removed. More details about this change.

     <button class="MuiTab-root">
    -  <span class="MuiTab-wrapper">
         {icon}
         {label}
    -  </span>
     </button>
    

TextField

  • Change the default variant from standard to outlined. Standard has been removed from the Material Design guidelines.

    โœ… This is handled in variant-prop codemod, read the details before running this codemod.

    -<TextField value="Standard" />
    -<TextField value="Outlined" variant="outlined" />
    +<TextField value="Standard" variant="standard" />
    +<TextField value="Outlined" />
    
  • Rename rowsMax prop with maxRows for consistency with HTML attributes.

    โœ… This is handled in the preset-safe codemod.

    -<TextField rowsMax={6}>
    +<TextField maxRows={6}>
    
  • Better isolate the fixed textarea height behavior to the dynamic one. You need to use the minRows prop in the following case:

    โœ… This is handled in the preset-safe codemod.

    -<TextField rows={2} maxRows={5} />
    +<TextField minRows={2} maxRows={5} />
    
  • Change ref forwarding expectations on custom inputComponent. The component should forward the ref prop instead of the inputRef prop.

    -function NumberFormatCustom(props) {
    -  const { inputRef, onChange, ...other } = props;
    +const NumberFormatCustom = React.forwardRef(function NumberFormatCustom(
    +  props,
    +  ref,
    +) {
      const { onChange, ...other } = props;
    
      return (
        <NumberFormat
          {...other}
    -     getInputRef={inputRef}
    +     getInputRef={ref}
    
  • Rename marginDense and inputMarginDense classes to sizeSmall and inputSizeSmall to match the prop.

    -<Input margin="dense" />
    +<Input size="small" />
    
  • Set the InputAdornment position prop to start or end. Use start if used as the value of the startAdornment prop. Use end if used as the value of the endAdornment prop.

    -<TextField startAdornment={<InputAdornment>kg</InputAdornment>} />
    -<TextField endAdornment={<InputAdornment>kg</InputAdornment>} />
    +<TextField startAdornment={<InputAdornment position="start">kg</InputAdornment>} />
    +<TextField endAdornment={<InputAdornment position="end">kg</InputAdornment>} />
    

TextareaAutosize

  • Remove the rows prop, use the minRows prop instead. This change aims to clarify the behavior of the prop.

    โœ… This is handled in the preset-safe codemod.

    -<TextareaAutosize rows={2} />
    +<TextareaAutosize minRows={2} />
    
  • Rename rowsMax prop with maxRows for consistency with HTML attributes.

    โœ… This is handled in the preset-safe codemod.

    -<TextareAutosize rowsMax={6}>
    +<TextareAutosize maxRows={6}>
    
  • Rename rowsMin prop with minRows for consistency with HTML attributes.

    โœ… This is handled in the preset-safe codemod.

    -<TextareAutosize rowsMin={1}>
    +<TextareAutosize minRows={1}>
    

ToggleButton

  • Move the component from the lab to the core. The component is now stable.

    โœ… This is handled in the preset-safe codemod.

    -import ToggleButton from '@mui/lab/ToggleButton';
    -import ToggleButtonGroup from '@mui/lab/ToggleButtonGroup';
    +import ToggleButton from '@mui/material/ToggleButton';
    +import ToggleButtonGroup from '@mui/material/ToggleButtonGroup';
    
  • span element that wraps children has been removed. label classKey is also removed. More details about this change.

     <button class="MuiToggleButton-root">
    -  <span class="MuiToggleButton-label">
         {children}
    -  </span>
     </button>
    

Tooltip

  • Tooltips are now interactive by default.

    The previous default behavior failed success criterion 1.4.3 ("hoverable") in WCAG 2.1. To reflect the new default value, the prop was renamed to disableInteractive. If you want to restore the old behavior (thus not reaching level AA), you can apply the following diff:

    -<Tooltip>
    +<Tooltip disableInteractive>
    
    # Interactive tooltips no longer need the `interactive` prop.
    -<Tooltip interactive>
    +<Tooltip>
    

Typography

  • Remove the srOnly variant. You can use the visuallyHidden utility in conjunction with the sx prop instead.

    +import { visuallyHidden } from '@mui/utils';
    
    -<Typography variant="srOnly">Create a user</Typography>
    +<span style={visuallyHidden}>Create a user</span>
    
  • The following classes and style overrides keys were removed: "colorInherit", "colorPrimary", "colorSecondary", "colorTextPrimary", "colorTextSecondary", "colorError", "displayInline" and "displayBlock". These props are now considered part of the system, not on the Typography component itself. If you still wish to add overrides for them, you can use the theme.components.MuiTypography.variants options. For example

    const theme = createTheme({
      components: {
        MuiTypography: {
    -     styleOverrides: {
    -       colorSecondary: {
    -         marginTop: '20px',
    -       },
    -     },
    +     variants: {
    +       props: { color: "secondary" },
    +       style: {
    +         marginTop: '20px',
    +       },
    +     }],
        },
      },
    });
    

Theme

  • The default background color is now #fff in light mode and #121212 in dark mode. This matches the Material Design guidelines.

  • Breakpoints are now treated as values instead of ranges. The behavior of down(key) was changed to define a media query below the value defined by the corresponding breakpoint (exclusive), rather than the breakpoint above. between(start, end) was also updated to define a media query for the values between the actual values of start (inclusive) and end (exclusive). When using the down() breakpoints utility you need to update the breakpoint key by one step up. When using the between(start, end) the end breakpoint should also be updated by one step up.

    โœ… This is handled in the preset-safe codemod.

    Here are some examples of the changes required:

    -theme.breakpoints.down('sm') // '@media (max-width:959.95px)' - [0, sm + 1) => [0, md)
    +theme.breakpoints.down('md') // '@media (max-width:959.95px)' - [0, md)
    
    -theme.breakpoints.between('sm', 'md') // '@media (min-width:600px) and (max-width:1279.95px)' - [sm, md + 1) => [0, lg)
    +theme.breakpoints.between('sm', 'lg') // '@media (min-width:600px) and (max-width:1279.95px)' - [0, lg)
    
    -theme.breakpoints.between('sm', 'xl') // '@media (min-width:600px)'
    +theme.breakpoints.up('sm') // '@media (min-width:600px)'
    

    The same should be done when using the Hidden component:

    -<Hidden smDown>{...}</Hidden> // '@media (min-width:600px)'
    +<Hidden mdDown>{...}</Hidden> // '@media (min-width:600px)'
    
  • The default breakpoints were changed to better match the common use cases. They also better match the Material Design guidelines. Read more about the change

    {
      xs: 0,
      sm: 600,
    - md: 960,
    + md: 900,
    - lg: 1280,
    + lg: 1200,
    - xl: 1920,
    + xl: 1536,
    }
    

    If you prefer the old breakpoint values, use the snippet below.

    import { createTheme } from '@mui/material/styles';
    
    const theme = createTheme({
      breakpoints: {
        values: {
          xs: 0,
          sm: 600,
          md: 960,
          lg: 1280,
          xl: 1920,
        },
      },
    });
    
  • The theme.breakpoints.width utility was removed because it's redundant. Use theme.breakpoints.values to get the same values.

    โœ… This is handled in the preset-safe codemod.

    -theme.breakpoints.width('md')
    +theme.breakpoints.values.md
    
  • The signature of theme.palette.augmentColor helper has changed:

    -theme.palette.augmentColor(red);
    +theme.palette.augmentColor({ color: red, name: 'brand' });
    
  • The theme.typography.round helper was removed because it was no longer used. If you need it, use the function below:

    โœ… This is handled in the preset-safe codemod.

    function round(value) {
      return Math.round(value * 1e5) / 1e5;
    }
    

@mui/types

  • Rename the exported Omit type in @mui/types. The module is now called DistributiveOmit. The change removes the confusion with the built-in Omit helper introduced in TypeScript v3.5. The built-in Omit, while similar, is non-distributive. This leads to differences when applied to union types. See this StackOverflow answer for further details.

    -import { Omit } from '@mui/types';
    +import { DistributiveOmit } from '@mui/types';
    

Migrate theme's styleOverrides to emotion

Although your style overrides defined in the theme may partially work, there is an important difference on how the nested elements are styled. The $ syntax used with JSS will not work with Emotion. You need to replace those selectors with a valid class selector.

Replace state class names

const theme = createTheme({
  components: {
    MuiOutlinedInput: {
      styleOverrides: {
        root: {
-         '&$focused': {
+         '&.Mui-focused': {
            borderWidth: 1,
          }
        }
      }
    }
  }
});

Replace nested classes selectors with global class names

const theme = createTheme({
  components: {
    MuiOutlinedInput: {
      styleOverrides: {
        root: {
-         '& $notchedOutline': {
+         '& .MuiOutlinedInput-notchedOutline': {
            borderWidth: 1,
          }
        }
      }
    }
  }
});

Note: For each component we export a [component]Classes constant that contains all nested classes for that component. You can rely on this instead of hardcoding the classes.

+import { outlinedInputClasses } from '@mui/material/OutlinedInput';

const theme = createTheme({
  components: {
    MuiOutlinedInput: {
      styleOverrides: {
        root: {
-         '& $notchedOutline': {
+         [`& .${outlinedInputClasses['notchedOutline']}`]: {
            borderWidth: 1,
          }
        }
      }
    }
  }
});

Take a look at the whole list of global state classnames available.

Migrate from JSS

This is the last step in the migration process to remove @mui/styles package from your codebase. We can use one of these two options, by order of preference:

1. Use styled or sx API

Codemod

We provide a codemod to help migrate JSS styles to styled API, but this approach increases the CSS specificity.

npx @mui/codemod v5.0.0/jss-to-styled <path>

Example transformation:

 import Typography from '@mui/material/Typography';
-import makeStyles from '@mui/styles/makeStyles';
+import { styled } from '@mui/material/styles';

-const useStyles = makeStyles((theme) => ({
-  root: {
-    display: 'flex',
-    alignItems: 'center',
-    backgroundColor: theme.palette.primary.main
-  },
-  cta: {
-    borderRadius: theme.shape.radius.
-  },
-  content: {
-    color: theme.palette.common.white,
-    fontSize: 16,
-    lineHeight: 1.7
-  },
-}))
+const PREFIX = 'MyCard';
+const classes = {
+  root: `${PREFIX}-root`,
+  cta: `${PREFIX}-cta`,
+  content: `${PREFIX}-content`,
+}
+const Root = styled('div')(({ theme }) => ({
+  [`&.${classes.root}`]: {
+    display: 'flex',
+    alignItems: 'center',
+    backgroundColor: theme.palette.primary.main
+  },
+  [`& .${classes.cta}`]: {
+    borderRadius: theme.shape.radius.
+  },
+  [`& .${classes.content}`]: {
+    color: theme.palette.common.white,
+    fontSize: 16,
+    lineHeight: 1.7
+  },
+}))

 export const MyCard = () => {
-  const classes = useStyles();
   return (
-    <div className={classes.root}>
+    <Root className={classes.root}>
       {/* The benefit of this approach is that the code inside Root stays the same. */}
       <Typography className={classes.content}>...</Typography>
       <Button className={classes.cta}>Go</Button>
-    </div>
+    </Root>
   )
 }

๐Ÿ’ก You should run this codemod per small chunk of files and then check the changes because in some cases you might need to adjust the code after the transformation (this codemod won't cover all of the cases).

We recommend sx API over styled when you have to create responsive styles or needs minor CSS overrides. Read more about sx.

 import Chip from '@mui/material/Chip';
-import makeStyles from '@mui/styles/makeStyles';
+import { styled } from '@mui/material/styles';

-const useStyles = makeStyles((theme) => ({
-  wrapper: {
-    display: 'flex',
-  },
-  chip: {
-    padding: theme.spacing(1, 1.5),
-    boxShadow: theme.shadows[1],
-  }
-}))
+const Root = styled('div')({
+  display: 'flex',
+})

 function App() {
-  const classes = useStyles();
   return (
-    <div>
-      <Chip className={classes.chip} label="Chip" />
-    </div>
+    <Root>
+      <Chip label="Chip" sx={{ py: 1, px: 1.5, boxShadow: 1 }} />
+    </Root>
   )
 }

Manual

In some cases, you might want to create multiple styled components in a file instead of increasing CSS specificity. for example:

-import makeStyles from '@mui/styles/makeStyles';
+import { styled } from '@mui/material/styles';

-const useStyles = makeStyles((theme) => ({
-  root: {
-    display: 'flex',
-    alignItems: 'center',
-    borderRadius: 20,
-    background: theme.palette.grey[50],
-  },
-  label: {
-    color: theme.palette.primary.main,
-  }
-}))
+const Root = styled('div')(({ theme }) => ({
+  display: 'flex',
+  alignItems: 'center',
+  borderRadius: 20,
+  background: theme.palette.grey[50],
+}))

+const Label = styled('span')(({ theme }) => ({
+  color: theme.palette.primary.main,
+}))

 function Status({ label }) {
-  const classes = useStyles();
   return (
-    <div className={classes.root}>
-      {icon}
-      <span className={classes.label}>{label}</span>
-    </div>
+    <Root>
+      {icon}
+      <Label>{label}</Label>
+    </Root>
   )
 }

Note: https://siriwatk.dev/tool/jss-to-styled is a tool that helps converting JSS to multiple styled components without increasing CSS specificity. (This tool is not maintained by MUI)

2. Use tss-react

The API is similar to JSS makeStyles but works with emotion.

Note: this library is not maintained by MUI. If you have any issue regarding to it, please open an issue in tss-react repository.

๐Ÿ’ก Once you migrate all of the styling, remove unnecessary @mui/styles by

npm uninstall @mui/styles

// or with `yarn`
yarn remove @mui/styles

Troubleshooting

Storybook emotion with v5

If your project use Storybook v6.x, you will need to update .storybook/main.js webpack config to use the most recent version of emotion.

// .storybook/main.js

const path = require('path');
const toPath = (filePath) => path.join(process.cwd(), filePath);

module.exports = {
  webpackFinal: async (config) => {
    return {
      ...config,
      resolve: {
        ...config.resolve,
        alias: {
          ...config.resolve.alias,
          '@emotion/core': toPath('node_modules/@emotion/react'),
          'emotion-theming': toPath('node_modules/@emotion/react'),
        },
      },
    };
  },
};

For more details, checkout this issue on GitHub.

Cannot read property scrollTop of null

This error comes from Fade, Grow, Slide, Zoom components due to missing DOM Node.

You need to make sure that the children forward ref to DOM for custom component.

// Ex. 1 โœ… html tag works since it is a DOM
<Fade in>
  <div>
    <CustomComponent />
  </div>
</Fade>

// Ex. 2 โŒ This will cause error. don't use Fragment as a child
<Fade in>
  <React.Fragment>
    <CustomComponent />
  </React.Fragment>
</Fade>;

// Ex. 3 โŒ This will cause error because `CustomComponent` does not forward ref to DOM
function CustomComponent() {
  return <div>...</div>;
}

<Fade in>
  <CustomComponent />
</Fade>;
// โœ… Fixed by using `React.forwardRef` and pass to DOM.
const CustomComponent = React.forwardRef(function CustomComponent(props, ref) {
  return (
    <div ref={ref}>
      ...
    </div>
  )
})

<Fade in>
  <CustomComponent />
</Fade>

For more details, checkout this issue on GitHub.

[Types] Property "palette", "spacing" does not exist on type 'DefaultTheme'

Since makeStyles is now exported from @mui/styles package which does not know about Theme in the core package. To fix this, you need to augment the DefaultTheme (empty object) in @mui/styles with Theme from the core. Read more about module augmentation

TypeScript Project

Put this snippet to your theme file:

// it could be your App.tsx file or theme file that is included in your tsconfig.json
import { Theme } from '@mui/material/styles';

declare module '@mui/styles/defaultTheme' {
  // eslint-disable-next-line @typescript-eslint/no-empty-interface (remove this line if you don't have the rule enabled)
  interface DefaultTheme extends Theme {}
}

Javascript Project

If your IDE (ex. VSCode) is able to infer types from d.ts file, create index.d.ts in your src folder with this snippet:

// index.d.ts
declare module "@mui/private-theming" {
  import type { Theme } from "@mui/material/styles";

  interface DefaultTheme extends Theme {}
}

[Jest] SyntaxError: Unexpected token 'export'

@mui/material/colors/red is considered private since v1.0.0. You should replace the import, more details about this error.

You can use this codemod (recommended) to fix all the import in your project:

npx @mui/codemod v5.0.0/optimal-imports <path>

or fix it manually like this:

-import red from '@mui/material/colors/red';
+import { red } from '@mui/material/colors';

makeStyles - TypeError: Cannot read property 'drawer' of undefined

This error occurs when calling useStyles (result of makeStyles) or withStyles outside of <ThemeProvider> scope like this:

import * as React from 'react';
import { ThemeProvider, createTheme } from '@mui/material/styles';
import makeStyles from '@mui/styles/makeStyles';
import Card from '@mui/material/Card';
import CssBaseline from '@mui/material/CssBaseline';

const useStyles = makeStyles((theme) => ({
  root: {
    display: 'flex',
    backgroundColor: theme.palette.primary.main,
    color: theme.palette.common.white,
  },
}));

const theme = createTheme();

function App() {
  const classes = useStyles(); // โŒ called outside of ThemeProvider
  return (
    <ThemeProvider theme={theme}>
      <CssBaseline />
      <Card className={classes.root}>...</Card>
    </ThemeProvider>
  );
}

export default App;

You can fix by moving useStyles inside another component so that it is called under <ThemeProvider>.

// ...imports

function AppContent(props) {
  const classes = useStyles(); // โœ… This is safe because it is called inside ThemeProvider
  return <Card className={classes.root}>...</Card>;
}

function App(props) {
  return (
    <ThemeProvider theme={theme}>
      <CssBaseline />
      <AppContent {...props} />
    </ThemeProvider>
  );
}

export default App;