packages/next/client/page-loader.js
function supportsPreload (list) {
  if (!list || !list.supports) {
    return false
  }
  try {
    return list.supports('preload')
  } catch (e) {
    return false
  }
}
function supportsPreload (list) {
  if (!list || !list.supports) {
    return false
  }
  try {
    return list.supports('preload')
  } catch (e) {
    return false
  }
}
smaller version of https://gist.github.com/igrigorik/a02f2359f3bc50ca7a9c