Core Changes

• Turbopack: Fix babel-loader (allowing built-in or manual configuration): #82676
• [Cache Components] allow using headers() in runtime prefetches: #83838
• [Breaking] Remove deprecated publicRuntimeConfig and serverRuntimeConfig: #83944
• Turbopack: mode to disable tracing: #83683
• babel-loader: Fix a few issues with config caching: #83973
• Turbopack: Merge babel-loader and react-compiler configuration logic to avoid running babel twice: #83502
• [breaking]: enable router scroll optimization by default: #84102
• Fix layout for ssgPageRoutes in the file tree: #84104
• Turbopack: Remove useless 'default' built-in webpack loader condition: #84111
• Fix: Client should auto reload after server restarts: #83971
• trace-build: Add missing spans: #84080
• Development: Remove TypeScript from the hot path during bootup: #84090
• Guide users to experimental.cacheComponents config: #84121

Misc Changes

• Turbopack: parallelize scope hoisting computation: #83904
• Add test for JS resource size on navigation: #83731
• Update Rspack development test manifest: #84061
• Update Rspack production test manifest: #84060
• Turbopack: Document automatic Babel config support: #84002
• docs: Fix the title/path of the turbopack page on pages router: #84001
• Turbopack: remove references from ChunkData: #84076
• Turbopack: include availability hash in the ident of evaluated chunks groups: #84082
• [turbopack] s/analyse/analyze/g: #84112
• [Turbopack] avoid attaching referenced output assets to chunks: #75933
• fix(docs): Fix links in UPGRADING.md: #84114
• docs: improve dynamic routes example in project structure page: #84086

Credits

Huge thanks to @bgw, @lubieowoce, @devjiwonchoi, @mischnic, @vercel-release-bot, @ztanner, @lukesandberg, @gaojude, @sokra, @timneutkens, @lachlanjc, @unstubbable, and @liketiger for helping!