Clear and concise description of the problem

Hi guys. The legacy plugin uses SystemJS which adds a 3kb> chunk. Since the legacy plugin itself is already adding code (due to polyfills of course), I'd like to see the ability to generate polyfills and run them via a simple IIFE. And also have the ability to merge polyfills to the legacy code (sometimes merge could be more suitable).

Suggested solution

I will shortly open a PR to extend the possibility of configuring this plugin to use the system or iife. And also a parameter to choose for a merge of polyfill and legacy code or not.

If I'm wrong, please tell me 👍

Alternative

No response

Additional context

No response

Validations

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