const entries = xhs.getPerformance && xhs.getPerformance().getEntriesByName("first-paint", "paint");

for (let i = 0, len = entries.length; i < len; i++) {
  console.log("entry name: " + entries[i].name);
  console.log("entry entryType: " + entries[i].entryType);
  console.log("entry startTime: " + entries[i].startTime);
  console.log("entry duration: " + entries[i].duration);
}