JSON sometimes doesn't have folding arrows.

What I see

I found that in my local development environment, there is no collapse arrow in front of some variables.

What I expect

I found that in online demo env(https://uiwjs.github.io/react-codemirror/#/extensions/languages), it works well.

How I use it

import CodeMirror from '@uiw/react-codemirror'; // https://github.com/uiwjs/react-codemirror
import { githubLight } from '@uiw/codemirror-theme-github'; // https://uiwjs.github.io/react-codemirror/#/theme/data/github/light
import {
  loadLanguage,
  langNames,
  langs,
} from '@uiw/codemirror-extensions-langs';

<CodeMirror
  value={data}
  readOnly={true}
  height="80vh"
  width="90vw"
  extensions={[githubLight, loadLanguage('json')]}
/>

"@uiw/codemirror-extensions-langs": "^4.22.2",
"@uiw/codemirror-theme-github": "^4.22.2",
"@uiw/react-codemirror": "^4.22.2",

Reproduce

codesandbox
Thanks in advance!

Start with the linked CodeSandbox reproduction and the JSON setup using loadLanguage('json'), then compare it with the online languages demo where folding works. Trace the CodeMirror JSON language and folding configuration to identify the environment difference; done means collapsible JSON variables consistently show folding arrows in the local reproduction.