Metadata formatDetection entries are ignored, value always set to no #83666
Description
Link to the code that reproduces this issue
https://codesandbox.io/p/devbox/currying-cdn-pvjzds?workspaceId=ws_6v27qQ9NbSp3MExEm6XtSh
To Reproduce
Add the following to any layout.js or app/page.js
export async function generateMetadata() {
return {
formatDetection: {
address: true,
email: true,
telephone: true,
},
};
}Current vs. Expected behavior
Current:
<meta name="format-detection" content="telephone=no, address=no, email=no">Expected:
<meta name="format-detection" content="telephone=yes, address=yes, email=yes">Provide environment information
Operating System:
Platform: darwin
Arch: arm64
Version: Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:29 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6000
Available memory (MB): 65536
Available CPU cores: 10
Binaries:
Node: 24.7.0
npm: 11.5.1
Yarn: 1.22.22
pnpm: N/A
Relevant Packages:
next: 15.5.2 // Latest available version is detected (15.5.2).
eslint-config-next: 15.3.2
react: 19.1.0
react-dom: 19.1.0
typescript: 5.8.2
Next.js Config:
output: N/AWhich area(s) are affected? (Select all that apply)
Metadata
Which stage(s) are affected? (Select all that apply)
next dev (local), next start (local), Other (Deployed)
Additional context
See canary code with hardcoded no value at https://github.com/vercel/next.js/blob/canary/packages/next/src/lib/metadata/generate/basic.tsx#L189