v15.3.0-canary.3

Core Changes

• Add config for only generating static env: #77038
• chore(HMR clients): Clean up and share code between app and pages router: #76960
• Add dev warning for cross-origin and stabilize allowedDevOrigins: #77044

Misc Changes

• fix(CI): Correctly call test/update-bundler-manifest.js script: #77000
• Update bundler development test manifest: #77040
• Update bundler production test manifest: #77043

Credits

Huge thanks to @bgw and @ijjk for helping!