legacy plugin: Functions not polyfilled (both modern and legacy) for code in a module web worker scripts about vite

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• vitejs-vite-s4so9k (Open reproduction)

[xuhdev]

While my interest is primarily in modern polyfill, the issue of legacy polyfill may also have some minor practical impact: The worker script should already be working in Chrome >= 80, while vite's browser support baseline is Chrome >= 87.

[xuhdev]

I found that manually adding the worker script to rollupOptions.input includes the polyfill:

  build: {
    rollupOptions: {
      input: ["index.html", 'src/worker.ts']
    }
  },

[xuhdev]

I take it back -- The above solution is incorrect, because vite would generate an additional worker-hash.js that is properly polyfilled, not the one that is being called as the worker script.

[xuhdev]

I found that adding the legacy plugin to the worker.plugins option does generate the polyfills for the worker script, but the generated polyfills aren't loaded anywhere.

worker: {
  plugins: () => [legacy({
      modernTargets: 'Chrome >= 100',
      modernPolyfills: true,
    })],
}