Introduction to Browserslist - Javascript

Browserslist is a tool that allows users to specify which browsers and their versions they want to support when writing CSS and JavaScript code. It reads a configuration file, and either returns the supported browsers as a string or an array, depending on how it's used.

Why use Browserslist?

Browserslist helps in the optimization of performance and compatibility of web applications by allowing developers to specify only the browsers they want to support while ignoring the rest. This can aid in the reduction of file sizes and the application of necessary polyfills where required.

How to use Browserslist?

Browserslist can be used in a number of ways, including; as a command line tool, a Node.js module, a PostCSS plugin or even with JavaScript. Here is an example of how it can be used with JavaScript:

const browserslist = require('browserslist');

const result = browserslist(['last 2 versions', 'ie >= 11']);

console.log(result);

This example will return an array of the browsers and their versions that meet the specified criteria. Here, it's asking for the last two versions of all popular browsers and Internet Explorer version 11 and above.

Configuration

Browserslist's configuration can be found in a dedicated browserslist file in the root directory of a project. Here is an example of how it can be configured:

# supported browsers (remember to house them in double-quotes if spaces are included)
"last 2 versions",
"ie >= 11"

# unsupported browsers
"ie <= 8""

Conclusion

Browserslist is a powerful tool that can greatly aid developers in maximizing web application performance while minimizing file sizes. Consider integrating Browserslist into your workflow to benefit from its powerful features.