TL;DR version: if you’re using webpack for a project and you’re getting this in the CLI (note the error on the last 3 lines) with yarn build or yarn run:
Yarn run v1.22.5
$ webpack --progress --config resources/assets/build/webpack.config.js
/bin/sh: /Users/giantpaper/Sites/~giantpaper.org/site/web/app/themes/giantphotos-2020/node_modules/.bin/webpack: Permission denied
error Command failed with exit code 126
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.