Working on something like a "draft" mode.
I have a JSON file for all pages with the 'published' flag.
On the home page, I assemble the page like this:

export async function getStaticProps({ locale, locales, draftMode }) {
    const data = await getPageData(locale, 'home');
    const globalProps = await getGlobalData(locale);
    console.log(data.published);
    if (!data.published && !draftMode) {
        return {
            notFound: true,
        };
    }

    const props = {
        data,
        globalProps,
        locales,
    };

    if (draftMode !== undefined) {
        props.draftMode = draftMode;
    }

    return {
        props,
        revalidate: 1,
    };
}

On other dynamic pages, I do it like this:

export async function getStaticProps({ params, locale, locales, draftMode }) {
    const data = await getPageData(locale, params.slug);
    const globalProps = await getGlobalData(locale);
    console.log('kek:', data.published, draftMode);

    if (!data.published && !draftMode) {
        return {
            notFound: true,
        };
    }

    const props = {
        data,
        globalProps,
        locales,
    };

    if (draftMode !== undefined) {
        props.draftMode = draftMode;
    }

    return {
        props,
        revalidate: 1,
    };
}

export async function getStaticPaths({ locales }) {
   ...
}

So, if the 'published' flag is false, I don't include it in the initial application build. However, if it's false and 'draftMode' is true, then I show these pages.

But for some reason, the version with the 'published' flag (previously, I was just filtering by language and draft mode) doesn't work on Vercel, although it works locally and in dev mode, and in the built version (npm run build -> npm run start).

What am I missing?