* Use core-js promise polyfill for nomodule browsers

Also updated to the core-js@3 features modules instead of importing the exact modules directly.

Fixes #10966

* Simplify reflect and regexp

* Add ie11 test for bad Promise

* Add test script for regexp and ie11
Co-authored-by: NJJ Kasper <jj@jjsweb.site>
Co-authored-by: NJoe Haddad <joe.haddad@zeit.co>

* Example with-react-relay-network-modern: update dependencies

* Example with-react-relay-network-modern: move relay __generated__ out of pages dir

* Example with-react-relay-network-modern: fix some errors

- Without checking if props.allBlogPosts exists it fails sometimes on
  "TypeError: Cannot read property 'edges' of undefined"

- I have no idea how it could work before with Component.query().params.name,
  but maybe some dependent library API has changed

* Example with-relay-modern-server-express: update dependencies

* Example with-relay-modern-server-express: move relay __generated__ out of pages dir

Fixes Error: Build optimization failed: found page without a React Component as default export in
pages/__generated__/pages_indexQuery.graphql

* Example with-relay-modern: update dependencies

* Example with-react-relay-network-modern: fix prettier errors

* Make sure to not show pages/404 GIP error from _app having GIP

* Add error for getStaticProps in pages/404 too

* fix missing open parenthesis

* Apply suggestions from code review
Co-Authored-By: NJJ Kasper <jj@jjsweb.site>
Co-authored-by: NJJ Kasper <jj@jjsweb.site>

* Update handling for unnamed params and named patterns in custom-routes

* Update query handling to match Now

* Add missing words

* Update docs/basic-features/data-fetching.md
Co-Authored-By: NJJ Kasper <jj@jjsweb.site>
Co-authored-by: NJJ Kasper <jj@jjsweb.site>
Co-authored-by: NJoe Haddad <joe.haddad@zeit.co>

* Correctly Count Object References

* Make error message better

* add more tests

* Verify GS(S)P Serializability

* Add support for cyclic refs

* Add unit tests

* Test for error in development mode

* Fix prerender preview tests

* Fix gssp preview tests

* fix 2x test cases

* Add desired test

* fix some more tests

* Fix route manifest expect

* Fix test expects

* Test that `getServerSideProps` does not error in production

* Test that getStaticProps is not checked in production

* Test serialization check during build

* Fix export detection for serverless

* Update test/unit/is-serializable-props.test.js
Co-Authored-By: NJJ Kasper <jj@jjsweb.site>
Co-authored-by: NJJ Kasper <jj@jjsweb.site>

Co-authored-by: NJJ Kasper <jj@jjsweb.site>

Fixes #10890

* Copy cms-datocms

* Update package.json

* Desktop design

* Tablet support

* Mobile styles

* Update titles

* Add article page

* Minor tweaks

* Fix height issue

* Improve text colors

* Extract Alert and Footer components

* Extract avatar

* Add Date

* Extract container

* Fix capitalization

* Make it work with no backend

* Add paragraph styles

* Extract PostPreview

* Extract h2

* Extract more stories

* Refactor into more components

* Update tags

* Add missing key

* Add custom document for lang="" support

* Add dotenv

* Load data for the index page

* Limit posts

* Show post page

* Add markdown processing

* Forgot margin

* Add links

* Remove files and add fallback

* Add og:image

* Add favicon

* Add aria-label

* Fix prerender

* Learn more → read documentation

* Fix links and footer

* Desaturate using imgix

* Add preview secret

* Add preview support

* Fix preview code

* Exit preview mode

* Extract getAllPostsWithSlug

* Extract getAllPostsForHome

* Extract getPreviewPostBySlug

* Extract getPostAndMorePosts

* Extract constants

* Extract markdownToHtml

* Fix markdown styles

* Fix imgix for author

* Add README

* Add links to docs

* Fix getStaticPaths example code

* Update docs/basic-features/data-fetching.md
Co-authored-by: NTim Neutkens <tim@timneutkens.nl>

* Add TypeScript docs

* Fix types

* Add preview mode file

* Update descriptions for data fetching

* Add preview mode documentation

* Use quotes for front matter

* Wordsmith

* Fix URL

* Minor updates
Co-authored-by: NTim Neutkens <timneutkens@me.com>

* Fix Prerender Test Cases

* fix test

* Fix `getServerSideProps` Test Case

* Data requests should fail instead of rendering

* Update to use separate export instead of attaching to Component to identify GS(S)P pages

* Handle initialProps being undefined

* add example for why-did-you-render

* Load whyDidYouRender from _app.js

To avoid custom webpack main entry modifications
as this can cause [hydration errors](https://github.com/zeit/next.js/pull/10662#pullrequestreview-365188433)

This reverts commit b5c70e86.

* update custom server readmes

* remove deploy buttons