@vitejs/plugin-legacy 

Vite's default browser support baseline is Native ESM, native ESM dynamic import, and import.meta. This plugin provides support for legacy browsers that do not support those features when building for production.

By default, this plugin will:

- Generate a corresponding legacy chunk for every chunk in the final bundle, transformed with @babel/preset-env and emitted as SystemJS modules (code splitting is still supported!).

- Generate a polyfill chunk including SystemJS runtime, and any necessary polyfills determined by specified browser targets and actual usage in the bundle.

- Inject