DisCoverage is a helpful extension for Chrome users that can analyze Javascript and CSS code for unused elements. It is designed for large scale sites and provides an overall view of the code as well as detailed insights about the content. 

Main features: 

Support for the latest JavaScript and CSS versions 

Ability to analyze multiple pages in one go 

Displays source and rendered codes as well as overall count of unused elements 

Provides a detailed breakdown of the code including a list of unused elements 

Supports the latest HTML versions Supports multiple files (one by one) 

Supports both JavaScript and CSS Ability to analyze the codes without opening your browser 

Supports multiple file types such as .js and.