JSFiddle - React, Tailwind, and code Playground

JavaScript

function getParameterByName(name, url) {
    if (!url) url = window.location.href;
    name = name.replace(/[\[\]]/g, "\\$&");
    var regex = new RegExp("[?&]" + name + "(=([^&#]*)|&|#|$)"),
        results = regex.exec(url);
    if (!results) return null;
    if (!results[2]) return '';
    return decodeURIComponent(results[2].replace(/\+/g, " "));
}

var googleFontUrl = 'https://fonts.googleapis.com/css?family=Droid+Serif:400,700,700i|Merriweather:300,400,700,900i|Open+Sans+Condensed:300,300i,700';
var fontFamilies = getParameterByName('family', googleFontUrl).split('|');
var fontArr = [];
fontFamilies.forEach(function(item) {
  fontArr.push(item.split(':')[0]);
});

alert(fontArr.join(', '));