* Add initial SSG fallback handling

* Remove extra changes and update fallback handling

* Remove extra timeout for testing

* Update SSG tests in dynamic-routing suite

* Add racing to decide between rendering fallback and data

* Update size-limit test

* Update comment

* Make sure to follow correct route change order

* Make comment more verbose for racing

* Revert getStaticData to only return Promise

* Make sure to update URL on fallback

* Add retrying for data, de-dupe initial fallback request, and merge fallback replace

* Update to add preload for fallback pages data

* Add test for data preload link

* Use pre-built fallback in production mode

* Remove preload link for fallback from _document

* Update to make sure fallback is rendered correctly for serverless

`@types/babel-types` doesn't seem to be in use anymore. `babel-types` is not used anywhere and `@babel/types` has its own typings included.

* Updated links

* Use default-example as the medium

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

* Update size-limit test to be more fine grained

* Decrease default build expected size

* Update failing diff amount to be 1kb

* Update to use existing util to de-dupe path check

* Update error message for requested/resolved mismatch

* Use correct dataRoute value for prerender manifest

* Fix pageUrl having double slash on Windows

* Wraps config in higher-order function

* De-dupe paths returned in getStaticPaths

* Remove warning

Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Re-enable `native-url`

* update sizes

* Modify splitChunksPlugin to give shared CSS chunks different names

* fix lint
Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Add support for rewriting to external resources

* Update rewrite proxying test
Co-authored-by: NTim Neutkens <tim@timneutkens.nl>
Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Remove `builds` from examples

* Fix with-zones example

* Run prettier on now.json

* Updated event

* adjust regex

* adjust regexp more

* Better test file regex

* add tests

* Update index.test.js

* Rename test file
Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Fix #8655, skip rendering meta tags with undefined props

* Filter all tags, not just meta

* Only render defined props

* Remove filtering of undefined strings
Co-Authored-By: NTim Neutkens <tim@timneutkens.nl>

* Replace Object.entries

* Remove filtering code

* Simplify code

* Add test

* Add tests for undefined head prop value and tweak check

* Update to strip undefined prop values to match react

* Update head.js
Co-authored-by: NTim Neutkens <tim@timneutkens.nl>
Co-authored-by: NJoe Haddad <timer150@gmail.com>
Co-authored-by: NJJ Kasper <jj@jjsweb.site>

* New Jest Example

* add missing zeit logo

* Revert zeit.svg

* remove old jest examples

* Update jest.config.js

* Add TypeScript Definitions for Sass

* fix test

* Update to not show API not ended warning when response is piped to

* Update to use res.once
Co-authored-by: NJoe Haddad <timer150@gmail.com>

Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Updated links

* Added utm
Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Fix bug in catch-all routes with SSG

* fix slash
Co-authored-by: NJoe Haddad <timer150@gmail.com>

* Changing variable name internally

* Add tests for custom AMP validator
Co-authored-by: NJJ Kasper <jj@jjsweb.site>

* Implement experimental pages/404.js for custom 404 page

* Make sure to show error for getInitialProps in pages/404 in dev mode also

* Update routes-manifest tests for new value

* Make sure page404 is boolean in routes-manifest

* Rename variables for consistency

* Make sure to only use 404 page for 404 error

* Add failing test case

* Add check that dynamic route is API route in handleApiRequest

* Add support for runtimeConfigs in serverless mode

* Update test