fix(@angular/build): bundle polyfills to preserve execution order in dev server#32635
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alan-agius4 merged 1 commit intoangular:mainfrom Mar 2, 2026
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…dev server When using the development server with ESM, polyfills were built as a mix of bundled local files and external package imports. Due to ESM hoisting behavior, all top-level import statements are executed before any other code in the module. This caused polyfills that modify global state (like zone-flags.js) to run after the polyfills they were intended to configure (like zone.js), rendering the flags ineffective. This change ensures that all polyfills are bundled together into the single polyfills.js file when using the development server, matching the behavior of the production build and preserving the intended execution order. Closes angular#32632
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When using the development server with ESM, polyfills were built as a mix of bundled local files and external package imports. Due to ESM hoisting behavior, all top-level import statements are executed before any other code in the module. This caused polyfills that modify global state (like zone-flags.js) to run after the polyfills they were intended to configure (like zone.js), rendering the flags ineffective.
This change ensures that all polyfills are bundled together into the single polyfills.js file when using the development server, matching the behavior of the production build and preserving the intended execution order.
Closes #32632