Autoprefixer 5.0 uses PostCSS 4.0 and Browserslist. Browserslist Browserslist is a library to parse browsers queries like last 2 versions. It gives to Autoprefixer: More accurate usage statistics calculation. New > 5% in US query to select browsers by usage statistics in some country. Global browserslist config. It is used in many other tools like Autopolyfiller or doiuse. Now you have one place t