get query-string parameters (alternative to `URLSearchParams`)

qs.js

var queryParams = window.location.search.substr(1).split('&').reduce(function (qs, query) {
  var chunks = query.split('=');
  var key = chunks[0];
  var value = decodeURIComponent(chunks[1] || '');
  var valueLower = value.trim().toLowerCase();
  if (valueLower === 'true' || value === 'false') {
    value = Boolean(value);
  } else if (!isNaN(Number(value))) {
    value = Number(value);
  }
  return (qs[key] = value, qs);
}, {});