Hi,

The build step in App Router, does a strict check on what is exported from a page.tsx or page.jsx, or page.js, file.

In your case, you are exporting Container, but that is not allowed. You can have a:

• default export,
• you can export generateStaticParams,
• you can export metadata or generateMetadata
• or any of the route segment config options, https://nextjs.org/docs/app/api-reference/file-conventions/route-segment-config
• and I think there might be a few others

You will likely need to use export {viewport} from 'next-sanity/studio/viewport' instead: https://github.com/sanity-io/next-sanity/blob/main/packages/next-sanity/MIGRATE-v6-to-v7.md#the-deprecated-next-sanitystudiohead-export-has-been-removed. I will recommend reaching out to Sanity Studio support team once.

Hello,

Thank you for the quick response. I have tried using export {viewport} from 'next-sanity/studio/viewport', but that was deprecated in v9 and the recommendation is to use export {viewport} from 'next-sanity/studio', per https://github.com/sanity-io/next-sanity/blob/main/packages/next-sanity/MIGRATE-v8-to-v9.md

One thing I forgot to mention is that this only happens with preview builds, production builds are fine. Are these errors ignored for production builds? I've tried excluding src/app/studio in tsconfig.json with no luck either.