[Bug] Static metadata (export const metadata) rendered in <body> instead of <head> in 15.5.4 #84750
Description
Link to the code that reproduces this issue
https://github.com/fabiotheo/nextjs-metadata-bug
To Reproduce
Step 1: Clone the reproduction repository
git clone https://github.com/fabiotheo/nextjs-metadata-bug
cd nextjs-metadata-bug
npm install
Step 2: Start development server
npm run dev
Step 3: Inspect HTML
1. Open http://localhost:3000
2. Open DevTools (F12)
3. Inspect the HTML structure
4. Search for meta tags (e.g., og:title, fb:app_id, twitter:card)
5. Notice all meta tags are rendered inside <body> instead of <head>
### Current vs. Expected behavior
```markdown
## Current Behavior (15.5.4) - BROKEN ❌
All metadata tags defined via `export const metadata` are incorrectly rendered **inside `<body>`** instead of `<head>`:
```html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Only basic Next.js meta tags, no custom metadata -->
</head>
<body>
<!-- ❌ WRONG: All custom metadata appears here -->
<title>Test App</title>
<meta name="description" content="Testing metadata bug in Next.js 15.5.4">
<meta property="og:title" content="Test App">
<meta property="fb:app_id" content="123456789">
<meta name="twitter:card" content="summary_large_image">
<!-- etc. -->
</body>
</html>
Expected Behavior (15.2.4) - CORRECT ✅
All metadata tags should be rendered inside <head>
Impact
This bug causes severe SEO and social sharing issues:
1. Open Graph broken: Facebook, LinkedIn, WhatsApp ignore meta tags in <body>
2. Twitter Cards broken: Twitter expects meta tags in <head>
3. SEO issues: Search engines may not properly parse metadata from <body>
4. HTML validation fails: Meta tags in <body> violate W3C standards
### Provide environment information
```bash
Operating System:
Platform: darwin
Arch: arm64
Version: Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:30 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6020
Available memory (MB): 32768
Available CPU cores: 10
Binaries:
Node: 22.19.0
npm: 10.9.3
Yarn: 1.22.22
pnpm: 10.17.1
Relevant Packages:
next: 15.5.4 // Latest available version is detected (15.5.4).
eslint-config-next: N/A
react: 19.2.0
react-dom: 19.2.0
typescript: 5.9.3
Next.js Config:
output: N/AWhich area(s) are affected? (Select all that apply)
Headers, Metadata
Which stage(s) are affected? (Select all that apply)
next dev (local), next build (local)
Additional context
Regression Details
The bug was introduced between versions:
- 15.2.4 (working) ✅
- 15.5.4 (broken) ❌
I have verified that downgrading to 15.2.4 completely resolves the issue.
Workaround
Temporarily downgrading to Next.js 15.2.4:
{
"dependencies": {
"next": "15.2.4"
}
}
Documentation Reference
From Next.js docs (https://nextjs.org/docs/app/api-reference/file-conventions/layout):
Good to know: You should not manually add <head> tags such as <title> and <meta> to root layouts. Instead, you should use the Metadata API.
The docs clearly state metadata should be in <head>, but 15.5.4 puts it in <body>.