Because your site has the Cross-Origin Embedder Policy enabled, each embedded iframe must also specify this policy

### Before opening, please confirm:

- [X] I have checked to see if my question is addressed in the [FAQ](https://github.com/aws-amplify/amplify-hosting/blob/master/FAQ.md).
- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-hosting/issues?q=is%3Aissue+).
- [X] I have read the guide for [submitting bug reports](https://github.com/aws-amplify/amplify-hosting/blob/master/CONTRIBUTING.md).
- [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.
- [X] I have removed any sensitive information from my code snippets and submission.

### App Id

d2hzcewjwit905

### AWS Region

eu-west-2

### Amplify Hosting feature

CDK, Custom headers

### Frontend framework

Next.js

### Next.js version

13.5.6

### Next.js router

App Router

### Describe the bug

My Next.js 13 app (https://main.d2hzcewjwit905.amplifyapp.com/) which uses [ffmpeg.wasm](https://github.com/ffmpegwasm/ffmpeg.wasm) tries to make a request to https://main.d2hzcewjwit905.amplifyapp.com/_next/static/chunks/795.ceab62a43c56068c.js when trying to convert a file. You can see this in the network tab. This gives the following error:


I'm not sure how to resolve this. I have set `Cross-Origin-Embedder-Policy` to `require-corp` for all paths in `next.config.js` (unless `source: "/(.*)"` doesn't match all paths? I tried `source: "/"` too and got the same issue).

The source code for my project which includes my `next.config.js` file can be found here: https://github.com/CrypticSignal/av-converter-amplify

### Expected behavior

I was expecting no COEP related issues as I have set the following in `next.config.js`:
```
async headers() {
return [
{
source: "/(.*)",
headers: [
{
key: "Cross-Origin-Embedder-Policy",
value: "require-corp",
},
{
key: "Cross-Origin-Opener-Policy",
value: "same-origin",
},
{
key: "Access-Control-Allow-Origin",
value: "*",
},
],
},
];
},
```

### Reproduction steps

1. Go to https://main.d2hzcewjwit905.amplifyapp.com
2. Open devtools and go to the network tab
3. Try to convert a file
4. After a few seconds, you should see a request being made to https://main.d2hzcewjwit905.amplifyapp.com/_next/static/chunks/795.ceab62a43c56068c.js and the following error:


### Build Settings

```yaml
version: 1
frontend:
phases:
build:
commands:
- yarn install
- yarn build
artifacts:
baseDirectory: .next
files:
- "**/*"
cache:
paths:
- node_modules/**/*
```

### Additional information

Platform: Web compute

The vercel deployed version works: https://av-converter-amplify.vercel.app

Therefore, Amplify and/or CloudFront is definitely the cause of the issue with the Amplify hosted version: https://main.d2hzcewjwit905.amplifyapp.com

I have also deployed a regular React version which doesn't use Next.js (https://main.d18xlq54508lji.amplifyapp.com) to check whether the issue is Next.js related. I get the same issue so the issue is not related to Next.js but rather caused by Amplify and/or CloudFront.

Start by reproducing the COEP error on the linked Amplify deployment and compare it with the working Vercel deployment. Inspect the linked project's next.config.js and the reported Amplify custom-header and Web Compute settings; done should identify whether Amplify or CloudFront is responsible and document a verified resolution or limitation.

Written by the indexing model from the issue text.