Corporate-starter does not populate, but gets deep nested response

Discord Q&A strapi-questions
1

I tried the GitHub - strapi/nextjs-corporate-starter: Strapi Demo application for Corporate Websites using Next.js template and it works great. The home page is fetched via http://localhost:1337/api/pages?filters[slug]=home&locale=en . According to populate documentation it should get only the first level of data, but gets a deep nested structure. How is this possible?

  "data": [
    {
      "id": 1,
      "attributes": {
        "shortName": "Home Page",
        "slug": "home",
        ...
        "locale": "en",
        "contentSections": [
          {
            "id": 1,
            "__component": "sections.hero",
            "title": "Strapi [Starter] with Next JS",
            "description": "This is build with [Strapi] and [Next] JS. A match made in heaven.",
            "picture": {
              "data": {```

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2

I think I found it, but do not understand it yet: page-populate-middleware.js seems to populate stuff backend side.