isCached = (src, type = 'js') => {
  const cache = window.fbLoaded[type]
  return (Array.isArray(src)) ? src.every(s => cache.includes(s)) : cache.includes(src)
}
Checks if remote resource is already loaded
@param  {string|Array} src  url of remote script or css
@param  {'js'|'css'}       [type='js']  type of remote resource
@return {boolean}      isCached