* Make sure to not show pages/404 GIP error from _app having GIP
* Add error for getStaticProps in pages/404 too
* Add support for getStaticProps in pages/404
* Update test
* Clean up landed experimental flags
* Remove check for experimental flags from build too
* Remove /_errors/404 in favor of /404
* Remove unneeded check for pathname
* Update test paths
* Fix test
* Update test
* Remove test for disabled config
* Set pages404 always to true
Co-authored-by: Joe Haddad <timer150@gmail.com>
Co-authored-by: JJ 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
