v4 webpack build error clsx not a function

[Falieson]

npm i -S @material-ui/styles@next @material-ui/core@next
> installs 4.0.0-alpha.0

Might be related to
#14152

• This is not a v0.x issue.
• I have searched the issues of this repository and believe that this is not a duplicate.

Expected Behavior 🤔

Trying to render the Paper example w/ the styles/ThemeProvider in 4.0.0

Current Behavior 😯

react-dom.development.js:19779 Uncaught TypeError: clsx__WEBPACK_IMPORTED_MODULE_5___default(...) is not a function
    at Paper (Paper.js:38)

  var className = clsx(classes.root, classes["elevation".concat(elevation)], _defineProperty({}, classes.rounded, !square), classNameProp);
  return React.createElement(Component, _extends({
    className: className,
    ref: ref
  }, other));
});

Steps to Reproduce 🕹

Adding material ui to a project initialized with https://github.com/TGRstack/typescript-graphql-react-app-express

// ThemeProvider.tsx
// DOC: https://material-ui.com/customization/themes/
import * as React from 'react'

import { createMuiTheme } from '@material-ui/core'
import indigo from '@material-ui/core/colors/indigo'
import pink from '@material-ui/core/colors/pink'
import red from '@material-ui/core/colors/red'
import MUIStylesProvider from '@material-ui/styles/ThemeProvider'

// tslint:disable object-literal-sort-keys
const theme = createMuiTheme({
  palette: {
    type: 'dark',
    primary: indigo,
    secondary: pink,
    error: red,
    // Used by `getContrastText()` to maximize the contrast between the background and
    // the text.
    contrastThreshold: 3,
    // Used to shift a color's luminance by approximately
    // two indexes within its tonal palette.
    // E.g., shift from Red 500 to Red 300 or Red 700.
    tonalOffset: 0.2,
  },
  spacing: 4,
  typography: {
    useNextVariants: true,
  },
})
// tslint:enable object-literal-sort-keys

//  DOC: https://material-ui.com/customization/themes/#muithemeprovider
const ThemeProvider = ({children}: {children: React.ReactChild}) =>  <MUIStylesProvider theme={theme}>
  {children}
</MUIStylesProvider>

export default ThemeProvider

// Home.tsx
import * as React from 'react'
import * as S from './Home.css'
import { Paper } from '_modules/skylo/mui/'
import Logo from './Logo'

function HomeEntrancePage() {
  return (
    <div className={S.container}>
      <Paper />
    </div>
  )
}

export default HomeEntrancePage

Context 🔦

Your Environment 🌎

Tech	Version
Material-UI	4.0.0-alpha.0
React	16.8.1
Browser	Chrome
TypeScript	3.3.1
etc.	999.999.999

[oliviertassinari]

It's a duplicate of #14512.

[Falieson]

Thanks @oliviertassinari