React - Browser error: fn.apply is not a function

Describe the bug Most of my components produce the following error in the browser. TypeError: fn.apply is not a function

To Reproduce Steps to reproduce the behavior:

1. npm run storybook
2. Error shows up in browser

Expected behavior No error, show my component

Screenshots

System:

Environment Info:

  System:
    OS: macOS 10.15.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 10.15.3 - ~/.nvm/versions/node/v10.15.3/bin/node
    Yarn: 1.19.0 - /usr/local/bin/yarn
    npm: 6.4.1 - ~/.nvm/versions/node/v10.15.3/bin/npm
  Browsers:
    Chrome: 78.0.3904.97
    Safari: 13.0.3
  npmPackages:
    @storybook/react: ^5.2.6 => 5.2.6 

[tonyjmartinez]

Found my problem… I wasn’t exporting a proper React component. This export const card = <Card>This is a card</Card>; Should have been this export const card = () => <Card>This is a card</Card>;

[XingXiaoWu]

same question. but it looks like can’t use Upper Camel Case just like

export const Basic = () => ({...})

when I use little camel-case

export const basic = () => ({..})

it’s ok.