This will reduce the bundle size and also give user proper hint to upgrade to `head.js`
* Mark `next/head` as noop in app dir
* Add warning for users to check the upgration guide to migrate it to head.js
As @timneutkens pointed out [here](https://github.com/vercel/next.js/pull/43819#discussion_r1042408158), changing the key will make Flight's module cache grow indefinitely. While I've thought about updating Flight's logic to clean the cache at some point, but that's tricky to do correctly as everything is asynchronous and we have to trigger clean up from outside (Webpack).
So currently, a better way I can think of is to just give Flight a proxied object as `moduleExports`. Even if Flight is getting the same object from cache, it will always require the latest module from Webpack.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] [e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs) tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Updated version of the reverted https://github.com/vercel/next.js/pull/43511
Unhandled errors that did not occur during React rendering (those errors are caught in `getDerivedStateFromError` in the Error Overlay) should be opened in the minimized toast state instead of fullscreen. For example if they occur in event handlers or setTimeout. Errors that breaks the app, such as uncaught render errors or build errors, still opens up in fullscreen mode.
The added test make sure the errors opens up as minimized, but if there's a breaking error it should "win" and open up in fullscreen. The updated tests either throw errors inside an event handler or a setTimeout, or the error is handled in a custom error boundary - which means the app don't break.
Closes NEXT-128
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] [e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs) tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
### Summary
Migrate `next/dynamic` to implementation based on `React.lazy` and
`Suspense`. Then it becomes easier to migrate the existing code in pages
to layouts. Then we can support both `ssr` and `loading` option for
`next/dynamic`.
For `loading` option, it will work like `Suspense`'s `fallback` property
```js
<Suspense fallback={loading}>
<DynamicComponent />
</Suspense>
```
For `ssr` option, by default `React.lazy` supports SSR, but we'll
disable the `ssr: false` case for dynamic import in server components
since there's no client side involved.
Then we don't need `suspense` option anymore as react >= 18 is always
required. Mark it as deprecated.
It also supports to load client component dynamically in server
components now.
#### Code code changes
* switch loadable component to `lazy` + `Suspense`
* will make sure it's retuning a module from `loader()` to
`loader().then(mod => ({ default: mod.default || mod }))` since `lazy()`
only accepts loader returning a module
* Inside suspense boundary, throwing an error for ssr: false, catch the
error on server and client side and ignore it.
* Ignore options like ssr: false for server components since they're on
server, doesn't make sense
* Remove legacy dynamic related transform
#### Feature changes
* `next/dynamic` will work in the same way across the board (appDir and
pages)
* For the throwing error, will make it become a API that throws error
later in the future, so users can customize more with `Suspense`
* You can load client components now in server components with dynamic.
Resolves#43147
#### Tests
* existing dynamic tests all work
* add case: import client component and load through next/dynamic in
server components
### Issues
Reverts vercel/next.js#43597
The tests were disabled and currently the checking of these components
are not reliable, it also breaks the hmr. Revert it for now and then
we'll revisit how to re-enable the required tags checking
There has been a few complaints about memory usage of the Next.js 13 dev server. One of the reasons why is that prefetching is always enabled when a link is visible on app routes (and not on pages). Disabling this behaviour, whilst keeping prefetching on hover/click, should help improve resources usage.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [x] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] [e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs) tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see [`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
### Update
We removed the `<head>` element checking for root layout in #41621. Since we also need `<head>` for preload in the future, and also css-in-js will require that. We're adding back the `head` element checking to make sure user always provide valid root layout including it.
### Issue
An issue was reported [here](https://github.com/mui/material-ui/issues/34905#issuecomment-1331945868) that the Emotion/MUI site was suffering from FOUC.
After an inspection, I noticed that the SSRed HTML didn't contain the inserted styles at all - despite them being inserted through `useServerInsertedHTML`. I managed to debug it down and discovered that their layout was missing `<head></head>` and thus the stream transformer skipped the insertion altogether cause of this check:
fbc98abab3/packages/next/server/node-web-streams-helper.ts (L177-L183)
I've figured that at the very least we could surface this as a console error in development to nudge the user to fix the missing `<head/>`
cc @huozhi
Co-authored-by: Jiachi Liu <4800338+huozhi@users.noreply.github.com>
fixes#43392
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## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [] Related issues linked using `fixes #number`
- []
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: JJ Kasper <jj@jjsweb.site>
This PR remove `React.useState()` from the `next/image` component. It
was only used in the `onError` case and it was causing Safari to become
very slow when there were many images on the same page. We were seeing
1s delay blocking the main thread when there were about 350 images on
the same page. Chrome and Firefox were not slow.
Add ref forwarding for next/image with integration test
- fixes https://github.com/vercel/next.js/discussions/42885
- fixes https://github.com/vercel/next.js/issues/18398 (this one was closed with `onLoadingComplete`)
## Feature
- [x] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Documentation added
Co-authored-by: Steven <229881+styfle@users.noreply.github.com>
Use `WellKnownErrorsPlugin` when formatting `@next/font` errors.
The error handling is different for expected errors (like validation
errors) and unknown ones. If the error is expected it just displays the
formatted error message. If it's an unknown error it will also display
the stacktrace, and in case the versions of `@next/font` and `next` are
different it will encourage you to try to update them both.
Removes the usage of `error-loader` when importing from
`pages/_document.js`, handle that case with `WellKnownErrorsPlugin` as
well.
The current warning when using different versions is removed. If the
versions are incompatible you'll get an error in the overlay instead.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
After upgrading to Next.js 13, we started seeing the following HMR
errors:
```sh
$ next dev
# ...
warn - Fast Refresh had to perform a full reload. Read more: https://nextjs.org/docs/basic-features/fast-refresh#how-it-works
TypeError: Cannot read properties of null (reading 'length')
at eval (webpack-internal:///./node_modules/next/dist/client/dev/error-overlay/hot-dev-client.js:262:55)
```
This error appears related to the changes made in
https://github.com/vercel/next.js/pull/42350 (cc @alexkirsz). It appears
that `module.hot.check` will pass `null` when there are no updates:
```ts
/**
* Throws an exceptions if status() is not idle.
* Check all currently loaded modules for updates and apply updates if found.
* If no update was found, the callback is called with null.
* If autoApply is truthy the callback will be called with all modules that were disposed.
* apply() is automatically called with autoApply as options parameter.
* If autoApply is not set the callback will be called with all modules that will be disposed on apply().
* @param autoApply
*/
check(autoApply?: boolean): Promise<null|ModuleId[]>;
```
When `updatedModules` is `null`, we skip the `apply()` call as this was
producing `apply() is only allowed in ready status (state: idle)`
errors. This matches [the prior behavior when `autoApply` was
enabled](8241da7f1e/lib/hmr/HotModuleReplacement.runtime.js (L266-L272)).
Fixes#43143. Also reported on Stack Overflow:
-
https://stackoverflow.com/questions/74415937/nextjs-typeerror-cannot-read-properties-of-null-reading-length
-
https://stackoverflow.com/questions/74504229/nextjs-v-13-typeerror-cannot-read-properties-of-null-reading-length
I tested this change locally and no longer see these HMR errors.
## Bug
- [X] Related issues linked using `fixes #number` - no related issues
- [X] Integration tests added - there aren't any existing tests, afaict
- [X] Errors have a helpful link attached, see `contributing.md` - N/A
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Do not directly import app-render into base-server since base-server is
shared module for both nodejs SSR and edge SSR.
Co-authored-by: JJ Kasper <jj@jjsweb.site>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
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The PR closes#42003.
Replace `(e: any) => void` with
`React.MouseEventHandler<HTMLAnchorElement>` and
`React.TouchEventHandler<HTMLAnchorElement>`. The original typing
overlap issue has also been fixed.
## Bug
- [x] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
Fixes
https://github.com/vercel/next.js/pull/42735#discussion_r1019116319.
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## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Solves the case where you click a link to the page you're on already that pushes additional history entries, uses replaceState for that instead. This mirrors the default `<a>` behavior.
## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Ensures the searchParams do not get removed when the page is static.
Fixes#42697
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## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
- [x] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Cases like `next/link` and `next/router` imports are not alias since
they're not matching the existing alias pattern setting for edge
runtime, which causes router-context being bundled twice (both with cjs
and esm) into edge worker bundle.
so we resolve their paths and alias them to esm bundle for webpack
bundling.
Other minor changes:
* update `require` calls to `import` expressions in edge ssr loaders
* remove client layer for apps without `appDir` enabled
* export `type` for ts typings in next/image to avoid alias to break
resolving
## Bug
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
The HTML `<link>` element's `onerror` function receives an Event-shaped object. The rejection here expects an `Error` shaped object. This PR 1:1 adopts the same pattern for `<link>` `onerror` that `script` `onerror` uses.
Attached you'll see an image that demonstrates that it _can_ end up in this state from turbo.build's Sentry logs:
<img width="919" alt="Screen Shot 2022-11-09 at 2 43 11 AM" src="https://user-images.githubusercontent.com/20542/200648928-12b85642-c9b5-4d7e-b4fe-2b2d420a6669.png">
This PR ensures that in app dir, styles imported in loading.js,
error.js, not-found.js, and template.js are properly handled and
rendered together with these components.
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
Co-authored-by: Tim Neutkens <tim@timneutkens.nl>
`globalThis` is available since node12 which becomes a preferrence
rather than `global`. Besides, in the client components like
`next/image` or async hooks we should prefer to use `globalThis` since
`global` isn't available in browser
Removes the `_` prefix from the RSC and Router headers as nginx strips
`_` prefixed headers by default.
Fixes#42164
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## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
The current `setTimeout` logic adds a constant overhead of 30ms when applying updates, which slows down HMR. As @sokra suggested, we can use the `addStatusHandler` API to have the HMR runtime let us know when its status changes. This also switches to `Promise.resolve` for update aggregation.
Accidentally returned `true` in this case whereas all others are
`false`.
Fixes
https://github.com/vercel/next.js/discussions/41745#discussioncomment-4075803.
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## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
After speaking with @timneutkens, this PR provides a smoother experience to users trying to migrate over to app without affecting users in pages.
This PR adds a new export available from `next/compat/router` that exposes a `useRouter()` hook that can be used in both `app/` and `pages/`. It differs from `next/router` in that it does not throw an error when the pages router is not mounted, and instead has a return type of `NextRouter | null`. This allows developers to convert components to support running in both `app/` and `pages/` as they are transitioning over to `app/`.
A component that before looked like this:
```tsx
import { useRouter } from 'next/router';
const MyComponent = () => {
const { isReady, query } = useRouter();
// ...
};
```
Will error when converted over to `next/compat/router`, as `null` cannot be destructured. Instead, developers will be able to take advantage of new hooks:
```tsx
import { useEffect } from 'react';
import { useRouter } from 'next/compat/router';
import { useSearchParams } from 'next/navigation';
const MyComponent = () => {
const router = useRouter() // may be null or a NextRouter instance
const searchParams = useSearchParams()
useEffect(() => {
if (router && !router.isReady) {
return
}
// In `app/`, searchParams will be ready immediately with the values, in
// `pages/` it will be available after the router is ready.
const search = searchParams.get('search')
// ...
}, [router, searchParams])
// ...
}
```
This component will now work in both `pages/` and `app/`. When the component is no longer used in `pages/`, you can remove the references to the compat router:
```tsx
import { useSearchParams } from 'next/navigation';
const MyComponent = () => {
const searchParams = useSearchParams()
// As this component is only used in `app/`, the compat router can be removed.
const search = searchParams.get('search')
// ...
}
```
Note that as of Next.js 13, calling `useRouter` from `next/router` will throw an error when not mounted. This now includes an error page that can be used to assist developers.
We hope to introduce a codemod that can convert instances of your `useRouter` from `next/router` to `next/compat/router` in the future.
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
x-ref: [slack
thread](https://vercel.slack.com/archives/C035J346QQL/p1667504961058549)
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
This changes the API of `usePathname` to return `string | null` to
support hybrid use-cases where the pathname is unknown at build time
(during automatic static optimization and when fallback is set true with
dynamic parameters in the pathname).
This supports a cleaner DX experience for those moving from `pages/` to
`app/` so they can begin to use `usePathname` in components that are
shared across them.
Since `useRouter()` can still be used in `pages` alone and should always
be a valid instance we shouldn't change the default return type to avoid
a breaking type change.
Fixes: https://github.com/vercel/next.js/issues/42409
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
When `useSelectedLayoutSegment` is used on the current level or in a
page it should return null.
fixes#41879fixes#41878
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
