postcss.config.js
Without any configuration options, PostCSS Preset Env enables Stage 2 features and supports all browsers.
The stage option determines which CSS features to polyfill, based upon their stability in the process of becoming implemented web standards.
plugins: {
"postcss-preset-env": {
stage: 2
}
}
The stage can be 0 (experimental) through 4 (stable), or false. Setting stage to false will disable every polyfill. Doing this would only be useful if you intended to exclusively use the features option.
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