`modulepreload` polyfill ends up in vendor chunk about vite

[bluwy]

If you'd like to separate out the preload script from the jspdf chunk, you can configure something like this instead:

export default defineConfig({
  plugins: [react()],
  build: {
    rollupOptions: {
      output: {
        manualChunks: {
          jspdf: ['jspdf'],
          preload: ['\0vite/preload-helper.js'] // <-- put in its own chunk
        }
      }
    }
  }
})

Rollup's chunking behaviour doesn't guarantee that only files in jspdf will be included in the chunk. Some imports within jspdf requires preloading, so Rollup includes the preloading script together because it sees that it's part of jspdf too.

About build.modulePreload.polyfill: false not working, I think it's related to #13952. In short, we can't know if preloading may be needed for CSS, so we always inject it. We may need to update the docs about this at the meantime, but we can track this in the issue there.

Closing this one for now as its how Rollup chunks things.

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• vitejs-vite-evfakv (Open reproduction)

[umairkhalid-devsinc]

Still not fixed

[stefan-schweiger]

thanks for the hint how to manually chunk the preload code!