What's Changed

[!NOTE]
This release is backporting bug fixes and minor improvements. It does not include all pending features/changes on canary.

Support esmExternals in app directory

• Support esm externals in app router (#65041)
• Turbopack: Allow client components from foreign code in app routes (#64751)
• Turbopack: add support for esm externals in app dir (#64918)
• other related PRs: #66990 #66727 #66286 #65519

Reading cookies set in middleware in components and actions

• initialize ALS with cookies in middleware (#65008)
• fix middleware cookie initialization (#65820)
• ensure cookies set in middleware can be read in a server action (#67924)
• fix: merged middleware cookies should preserve options (#67956)

Metadata and icons

• support facebook-specific metadata (fb:app_id, fb:admins) in generateMetaData (#65713)
• Always collect static icons for all segments (#68712)
• Fix favicon merging with customized icons (#67982)
• Warn metadataBase missing in standalone mode or non vercel deployment (#66296)

Parallel routes fixes

• fix missing stylesheets when parallel routes are present (#69507)

Draft mode and edge improvements

• fix: unstable_cache should not cache new result in draft mode (#67772)
• Add draft mode flag for multi-zone (#68997)
• Fix edge preview props are not matched with cookie (#67779)
• other related PRs: #65426, #67787, #64946, #64313, #64370

next/image fixes

• Allow external image urls with _next/image pathname to be rendered via Image component (#69586)

Server actions improvements

• optimize server actions (#66523)
• Apply optimization for unused actions (#69178)
• Improve SWC transform ID generation (#69183)

Other changes

• Ensure we match comment minify behavior between terser and swc (#68372)
• send initialCanonicalUrl in array format to prevent crawler confusion (#69509)

Create-next-app updates

• enable @typescript-eslint/recommended in create-next-app --typescript (#52845)
• Update create-next-app template CSS (#66233)
• Update create-next-app template CSS (#66043)
• Update create-next-app template (#65803)
• add font antialiasing to templates (#67425)
• Move create-next-app public/ assets from local folder→ remote URL (#66931)
• Use classnames to set font family in Tailwind create-next-app templates (#66374)
• other related PRs: #64478, #68899, #68534, #69021, #67146, #66145

Full Changelog: https://github.com/vercel/next.js/compare/v14.2.7...v14.2.8

Huge thanks to everyone who contributed to this release: @abhi12299, @delbaoliveira, @eps1lon, @ForsakenHarmony, @huozhi, @ijjk, @JoshuaKGoldberg, @leerob, @lubieowoce, @Netail, @ronanru, @samcx, @shuding, @sokra, @stylessh, @timfuhrmann, @wbinnssmith, @wyattjoh, @ypessoa, @ztanner