Merge branch 'canary' into feedthejim/next-1078-change-prefetch-heuri…

…stics-to-traverse

.github/ISSUE_TEMPLATE/1.bug_report.yml

@@ -53,8 +53,8 @@ body:
     attributes:
       label: Link to the code that reproduces this issue
       description: |
-        A link to a GitHub repository, a [CodeSandbox](https://codesandbox.io/p/sandbox/github/vercel/next.js/tree/canary/examples/reproduction-template) or a [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template) minimal reproduction. Minimal reproductions should be created from our [bug report template with `npx create-next-app -e reproduction-template`](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template) and should include only changes that contribute to the issue.
-        To report an App Router related issue, you can use these templates: [CodeSandbox](https://codesandbox.io/p/sandbox/github/vercel/next.js/tree/canary/examples/reproduction-template-app-dir), [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template-app-dir) or [`npx create-next-app -e reproduction-template-app-dir`](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir)
+        A link to a [GitHub repository](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template) or a [CodeSandbox](https://codesandbox.io/p/sandbox/github/vercel/next.js/tree/canary/examples/reproduction-template) minimal reproduction. Minimal reproductions should be created from our [bug report template with `npx create-next-app -e reproduction-template`](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template) and should include only changes that contribute to the issue.
+        To report an App Router related issue, you can use these templates: [CodeSandbox](https://codesandbox.io/p/sandbox/github/vercel/next.js/tree/canary/examples/reproduction-template-app-dir) or [`npx create-next-app -e reproduction-template-app-dir`](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir)
     validations:
       required: true
   - type: textarea

.github/actions/issue-validator/canary.md

@@ -10,7 +10,7 @@ If the issue does not reproduce with the `canary` version, then it has already b
 
 ### **How can I quickly verify if my issue has been fixed in `canary`?**
 
-The safest way is to install `next@canary` in your project and test it, but you can also search through [closed Next.js issues](https://github.com/vercel/next.js/issues?q=is%3Aissue+is%3Aclosed) for duplicates or check the [Next.js releases](https://github.com/vercel/next.js/releases). You can also use the GitHub [template](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template) (preferred), or the [CodeSandbox](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) or [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template) templates to create a reproduction with `canary` from scratch.
+The safest way is to install `next@canary` in your project and test it, but you can also search through [closed Next.js issues](https://github.com/vercel/next.js/issues?q=is%3Aissue+is%3Aclosed) for duplicates or check the [Next.js releases](https://github.com/vercel/next.js/releases). You can also use the GitHub templates (preferred) for [pages](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template) and [App Router](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir), or the [CodeSandbox: `pages`](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) or [CodeSandbox: App Router](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir) templates to create a reproduction with `canary` from scratch.
 
 ### **My issue has been open for a long time, why do I need to verify `canary` now?**
 

.github/actions/issue-validator/repro.md

@@ -2,7 +2,7 @@ We cannot recreate the issue with the provided information. **Please add a repro
 
 ### **Why was this issue marked with the `please add a complete reproduction` label?**
 
-To be able to investigate, we need access to a reproduction to identify what triggered the issue. We prefer a link to a public GitHub repository ([template](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template)), but you can also use a tool like [CodeSandbox](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) or [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template).
+To be able to investigate, we need access to a reproduction to identify what triggered the issue. We prefer a link to a public GitHub repository ([template for `pages`](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template), [template for App Router](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir)), but you can also use these templates: [CodeSandbox: `pages`](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) or [CodeSandbox: App Router](https://github.com/vercel/next.js/tree/canary/examples/reproduction-template-app-dir).
 
 To make sure the issue is resolved as quickly as possible, please make sure that the reproduction is as **minimal** as possible. This means that you should **remove unnecessary code, files, and dependencies** that do not contribute to the issue.
 

examples/reproduction-template-app-dir/README.md

@@ -34,8 +34,7 @@ To learn more about Next.js, take a look at the following resources:
 - [Learn Next.js](https://nextjs.org/learn) - an interactive Next.js tutorial.
 - [How to Contribute to Open Source (Next.js)](https://www.youtube.com/watch?v=cuoNzXFLitc) - a video tutorial by Lee Robinson
 - [Triaging in the Next.js repository](https://github.com/vercel/next.js/blob/canary/contributing.md#triaging) - how we work on issues
-- [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template) - Edit this repository on StackBlitz
-- [CodeSandbox](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) - Edit this repository on CodeSandbox
+- [CodeSandbox](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template-app-dir) - Edit this repository on CodeSandbox
 
 You can check out [the Next.js GitHub repository](https://github.com/vercel/next.js/) - your feedback and contributions are welcome!
 

examples/reproduction-template/README.md

@@ -33,7 +33,6 @@ To learn more about Next.js, take a look at the following resources:
 - [Learn Next.js](https://nextjs.org/learn) - an interactive Next.js tutorial.
 - [How to Contribute to Open Source (Next.js)](https://www.youtube.com/watch?v=cuoNzXFLitc) - a video tutorial by Lee Robinson
 - [Triaging in the Next.js repository](https://github.com/vercel/next.js/blob/canary/contributing.md#triaging) - how we work on issues
-- [StackBlitz](https://stackblitz.com/fork/github/vercel/next.js/tree/canary/examples/reproduction-template) - Edit this repository on StackBlitz
 - [CodeSandbox](https://codesandbox.io/s/github/vercel/next.js/tree/canary/examples/reproduction-template) - Edit this repository on CodeSandbox
 
 You can check out [the Next.js GitHub repository](https://github.com/vercel/next.js/) - your feedback and contributions are welcome!

packages/next/src/server/web/spec-extension/adapters/headers.ts

@@ -17,8 +17,14 @@ export class ReadonlyHeadersError extends Error {
   }
 }
 
-export type ReadonlyHeaders = Omit<Headers, 'append' | 'delete' | 'set'>
-
+export type ReadonlyHeaders = Headers & {
+  /** @deprecated Method unavailable on `ReadonlyHeaders`. Read more: https://nextjs.org/docs/api-reference/headers */
+  append(...args: any[]): void
+  /** @deprecated Method unavailable on `ReadonlyHeaders`. Read more: https://nextjs.org/docs/api-reference/headers */
+  set(...args: any[]): void
+  /** @deprecated Method unavailable on `ReadonlyHeaders`. Read more: https://nextjs.org/docs/api-reference/headers */
+  delete(...args: any[]): void
+}
 export class HeadersAdapter extends Headers {
   private readonly headers: IncomingHttpHeaders