querystring is not working to alternates canonical and languages in generateMetadata

Link to the code that reproduces this issue

https://github.com/richg0ld/generate-metadata-bug

To Reproduce

In Next.js 15, I am trying to use the query string in generateMetadata's alternates.canonical and alternates.languages, but it is not being applied.

How can I ensure that querystring is not removed?

The sample code is as follows.

export async function generateMetadata(): Promise<Metadata> {
  return {
    metadataBase: new URL('http://localhost:3000'),
    title: t('title'),
    alternates: {
      canonical: '/',
      languages: {
        'x-default': '/',
        en: '/?hl=en_US',
        ko: '/?hl=ko_KR',
      },
    },
  };
}

Current vs. Expected behavior

The expected behavior is as follows,

<link rel="alternate" hreflang="x-default" href="http://localhost:3000">
<link rel="alternate" hreflang="en" href="http://localhost:3000/?hl=en_US">
<link rel="alternate" hreflang="ko" href="http://localhost:3000/?hl=ko_KR">

However, the result is as follows,

<link rel="alternate" hreflang="x-default" href="http://localhost:3000">
<link rel="alternate" hreflang="en" href="http://localhost:3000">
<link rel="alternate" hreflang="ko" href="http://localhost:3000">

Provide environment information

nextjs:15.0.3
reactjs:19.0.0-rc
react-dom:19.0.0-rc

Which area(s) are affected? (Select all that apply)

Metadata

Which stage(s) are affected? (Select all that apply)

next dev (local), next build (local), next start (local), Other (Deployed)

Additional context

It would be helpful to have an 'other' option for link tags, similar to the 'other' option for handling meta tags. For example, having a method like this would be useful.

...,
other: [
  {
    hreflang: "en",
    rel: "alternate",
    href="/?hl=en_US"
  },
  ...
]

having a method like this would be useful.

vercel / next.js