Chrome developer toolbar util: Get CSS containing used CSS classes used below a specified selector

ChromeGetUsedClassesAsCSS.js

var allClasses = {}, css = '';
var startFrom = prompt('Where should I start?', '#application');
Array.prototype.forEach.call(document.querySelectorAll(startFrom+' *[class]'), function(element) {
  Array.prototype.forEach.call(element.classList, function(className) {
     if (!allClasses[className]) {
       allClasses[className] = 0;
     }
     allClasses[className]++;
  })
});
var found = 0;
for(var key in allClasses) {
  css+='.'+key+' {\n/* found '+allClasses[key]+' times */\n}\n';
  found++;
};
copy(css);
alert('Found '+found+' classes.\nCSS generated and copied to your clipboard')