drago.cc

A gist by Sindre Sorhus that explains a lot about ESM. I first saw this linked to from react-markdown's v7.0.0 change log, but it's probably a good document to link to from any pure ESM package.

Here's the gist: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c