optinout.js/src/helper/doNotTrack.js

a simple js framework for handling opt-in and opt-out for tracking & cookies

/* FROM: https://github.com/jhobz/dnt-polyfill */
/* eslint-disable */
const doNotTrack = () => {
  return Boolean(
    window && (
      // Internet Explorer 11 uses window.doNotTrack rather than navigator.doNotTrack.
      // Safari 7.1.3+ uses window.doNotTrack rather than navigator.doNotTrack.
      window.doNotTrack === '1' ||
      window.navigator && (
        window.navigator.doNotTrack === '1' ||
        // Prior to Gecko 32 Firefox would report navigator.doNotTrack with values of yes and no rather than 1 and 0.
        window.navigator.doNotTrack === 'yes' ||
        // Internet Explorer 9 and 10 use a vendor prefix, i.e. navigator.msDoNotTrack.
        window.navigator.msDoNotTrack === '1'
      )
    )
  );
};

export default doNotTrack;