Report browser performance timing and navigation data

report.js

function report() {
  try {
    return {
      userAgent: 'navigator' in window && navigator.userAgent,
      timing: 'performance' in window && performance.timing,
      navigation: 'performance' in window && performance.navigation,
      chrome: 'chrome' in window && chrome.loadTimes(),
      serviceWorker: 'serviceWorker' in navigator,
    };
  } catch (e) {};
}