Using this demo data, I confirm that on nextjs 15.5.2 the tags are moved at the end of body. it is due from the url present in these data

export async function generateMetadata({ params }: Props) {
const { locale } = await params
const t = await getTranslations({ locale, namespace: "homePage.meta" })

return {
metadataBase: new URL('https://example.com'),
title: { default: 'My Site', template: '%s | My Site' },
description: 'Welcome to My Site',
alternates: {
canonical: 'https://example.com',
languages: {
'en-US': 'https://example.com/en-US',
'de-DE': 'https://example.com/de-DE'
}
},
openGraph: {
title: 'My Site',
description: 'Welcome to My Site',
url: 'https://example.com',
siteName: 'My Site',
images: [{ url: 'https://example.com/og.png' }]
},
}
}


If now I use this data

export async function generateMetadata({ params }: Props) {
const { locale } = await params
const t = await getTranslations({ locale, namespace: "homePage.meta" })

return {
metadataBase: new URL('https://example.com'),
title: { default: 'My Site', template: '%s | My Site' },
description: 'Welcome to My Site',
openGraph: {
title: 'My Site',
description: 'Welcome to My Site',
siteName: 'My Site',
images: [{ url: 'https://example.com/og.png' }]
},
}
}


there are no problem and they appears in the head tag

I've tested with my data, but it has the same problems with default e basic data, so I think it is a bug