Security: due to supply chain attack, pollyfill JS removed

[delyriand]

cf https://sansec.io/research/polyfill-supply-chain-attack

Summary

As explain in the https://sansec.io/research/polyfill-supply-chain-attack, the Polyfill JS contains a malicious script.
And, like IE 9 and below, are very rarely used now:

Source: https://www.w3counter.com/trends

I suggest deleting the polyfill addition in layout

Result