PostCSS Browser Comments

npm install postcss-browser-comments --save-dev

PostCSS Browser Comments lets you keep only the CSS you need based on comments and your browserslist.

/**
 * Prevent adjustments of font size after orientation changes in IE and iOS.
 */

html {
  -ms-text-size-adjust: 100%;
  -webkit-text-size-adjust: 100%;
}

/* becomes */

The comment and rule above would be removed with the following browserslist:

last 2 chrome versions

The rule below would be more carefully altered:

/**
 * 1. Add the correct box sizing in Firefox.
 * 2. Show the overflow in Edge and IE.
 */

hr {
  box-sizing: content-box; /* 1 */
  height: 0; /* 1 */
  overflow: visible; /* 2 */
}

/* with a `last 2 firefox versions` browserslist becomes */

/**
 * 1. Add the correct box sizing in Firefox.
 * 2. Show the overflow in Edge and IE.
 */

hr {
  box-sizing: content-box; /* 1 */
  height: 0; /* 1 */
}

Usage

Add PostCSS Browser Comments to your project:

npm install postcss postcss-browser-comments --save-dev

Use it as a PostCSS plugin:

const postcss = require('postcss');
const postcssBrowserComments = require('postcss-browser-comments');

postcss([
	postcssBrowserComments(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);

Options

browsers

The browsers option overrides of the project’s browserslist.

postcssBrowserComments({ browsers: 'last 2 versions' })