React Invariant thrown during Next.js `next build`

With, `npm ls react` you can see `react@16.14.0` is **not deduped**, and everything else is on `react@17.0.2`

```
...
├─┬ react-dom@17.0.2
│ └── react@17.0.2 deduped
...
├─┬ react-live@2.4.0 (...same issue w/ 2.3.0)
│ ├─┬ prism-react-renderer@1.2.1
│ │ └── react@17.0.2 deduped
│ └─┬ react-simple-code-editor@0.11.0
│ ├─┬ react-dom@16.14.0 <-----------------not deduped
│ │ └── react@16.14.0 deduped
│ └── react@16.14.0 <-----------------not deduped
...
├── react@17.0.2
...
```

I _believe_ this is preventing my Next.js project from building, due to the [more than one copy of React](https://reactjs.org/warnings/invalid-hook-call-warning.html) React invariant.

... strangely it only happens when installing everything w/ `npm` and not `yarn`

---

Side: `react-simple-code-editor` https://github.com/satya164/react-simple-code-editor/blob/master/package.json#L62-L65 doesn't specify `react/-dom 17` as a peer dependency. (It also hasn't seen a new update in close to 2 years now :/)

Update: Opened a PR to allow react 17 as a peerDep
- https://github.com/satya164/react-simple-code-editor/pull/89

Start by reproducing the dependency tree with npm ls react and the failing Next.js next build, then compare the npm and Yarn installs. Inspect react-simple-code-editor/package.json and the referenced PR #89 concerning React 17 peer dependencies. Done means the build no longer throws the React invariant with compatible React versions resolved.

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