A tool which gives you a quick look at `font-family` usage in a webpage.
*fi* helps you learn font-family usage in a webpage. Texts inside these elements will be ignored: script, noscript, style, iframe, option. Invisible elements won't be taken into account as well, which includes those with opacity: 0, display: none and visibility: hidden. The result will sort all used font-family values by character numbers they apply to. ie. most used one will be at the top of the result list.