JavaScript & CSS Code Usage
See how much of each JavaScript & CSS file loaded on a page is actually used.
It's worth noting 100% usage is not a realistic goal for most websites. You can also use Chrome devTools, find out how here: Google devTools Doc
You can also download the JS / CSS files with just the used stuff, but be aware, these are not meant to be replacements, classes and functions may get missed, and replacing your sites files with these may very well break something!
URL is required
Uses these excellent open source projects: Puppeter