Source maps should be enabled in development so that original styles can be inspected.
This is in-line with other Next.js behavior (source maps in dev).

* Fixing page sizes displayed during build

* Adding comments

* Update variable name

* Fixed support for modern mode

* Remove braces

* Memoize fs.stat result

* Memoize fs.stat result

This simplifies the CSS insert function and fixes its edge cases around nextSibling by inserting before the anchor instead of after it.

* insert css *after* noscript tag in dev mode

* use arrow function

* Fix CSS Ordering
This fixes CSS ordering between development and production.

Before this change, globally imported CSS would come _after_ `<style jsx global>` in development, but _before_ in production.

After this change, it'll always be applied before.

* Move to correct element

* Add tests

* Fix obnoxious indents

* Update test/integration/css/fixtures/with-styled-jsx/pages/index.js
Co-Authored-By: NJJ Kasper <jj@jjsweb.site>

We were trying to be too tricky. `visibility: hidden` is great for layout speed, but it allows child elements to make themselves visible.

Since styles are going to change anyway, this doesn't make sense. We should completely hide the body which prevents a reflow by avoiding any style computation until Global CSS is ready to go.

* Reduce Install Size
This should shave a decent amount off our install size.

* Fix CSS source map emitting

* Fix generation

* Enable source maps for testing purposes

* Disable double comment

* Fix test regex

This is in preparation of a new plugin.

* Global CSS Support

* Fix webpack configuration

* oneOf rule isn't necessary yet

* Adjust CSS chunk naming

* Begin testing CSS behavior

* Add another test TODO

* Replace null-loader with ignore-loader

* Turn on chunks for new CSS feature

* Fix multi test suite

* Test CSS import order

* Test style HMR

* Test CSS compilation

* Test compilation and prefixing together

* Verify CSS styling works for Development and Production

* Add missing TODO

* Remove unnecessary test

* Adjust TODO message

* Hide page until React hydrates

* Revert "Hide page until React hydrates"

This reverts commit 898d4e0ee547b003d5790e2b11476740d645b907.

* Hide FOUC during development

* Test CSS imports

* Update tests TODO

* Add fixture for url() test

* Test `file-loader` support in CSS files

* Use a simple variant of cssnano

* Self-import

* Undo bundling

* Implement suggestion

* Match public files priority in dev

* Remove un-needed old public file handling

* Run public file priority test for non-dev also

* Make sure to enable publicDirectory

* Add checking for conflicting pages in dev and during build

* Add error for public dir middleware conflict

* Add err.sh for _next conflict

* Move up public dir conflict checking

* Only run _next conflict check in dev when path contains it

* Prevent updating URL when delaying asPath

* Ignore TypeScript not liking __NEXT_DATA__

* Update another global to fix standard check

* Add progress for analyzing and auto-prerendering

* Add typing for tty-aware-progress and use stdout

* Add fancier spinners

* Update spinner and add handling for logs while spinning

* Remove un-needed types package

* Remove progress and combine analyzing/prerendering messages

* Catch error from failing to unobserve

* Update link.tsx

* Convert Readme Custom Error Pages To Functional Component

* Update packages/next/README.md
Co-Authored-By: NTim Neutkens <tim@timneutkens.nl>

* Run readme through prettier

* Add link to docs for prerender indicator and allow disabling

* Fix lint error from example

* Disable by default when electron is detected

* Add button to dismiss indicator for session

* Update disabling indicator in electron

* Add autoExport to __NEXT_DATA__

* Update render variable

* Ensure requests are resolved as directories
`resolveRequest` will strip down to baseDir if there's no trailing slash as it assumes you passed a file.

* Disable telemetry for PR Stats

This fully annotates our externals code to explain how it should be functioning. This will be useful as tests cases are made to ensure this is working correctly.

* Make sure to error on serverless prerender failure

* Add test case

* Update index.test.js

* Make sure renderOpts is available before checking

* Apply suggestions from code review
Co-Authored-By: NJoe Haddad <joe.haddad@zeit.co>

* Update check