Why is Webpack swearing at the operator?

Question

webpack

There is this piece of code:

let concateUrlSearch = Object.entries(urlHash.split('&').reduce((acc, n) => (
           n = n.match(/(.*)=(.*)/),
           (acc[n[1]] ??= []).push(n[2]),
           acc
         ), {})).map(n => `${n[0]}=${n[1].join('|')}`);

Webpack throws this error. If I remove ??= or replace it with || , then everything works, but not as it should. Help solve it.

ERROR in ./src/js/components/Accordeon.js 68:23
Module parse failed: Unexpected token (68:23)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file.

Answer 1

If this is in the code, then include babel + preset-env
If this is in the webpack config itself, update the node to 16