Piwik\Plugins\PrivacyManager\DoNotTrackHeaderChecker::checkHeaderInTracker PHP Method

    public function checkHeaderInTracker(&$exclude)
    {
        if ($exclude) {
            Common::printDebug("Visit is already excluded, no need to check DoNotTrack support.");
            return;
        }
        $exclude = $this->isDoNotTrackFound();
        if ($exclude) {
            IgnoreCookie::deleteThirdPartyCookieUIDIfExists();
            // this is an optional supplement to the site's tracking status resource at:
            //     /.well-known/dnt
            // per Tracking Preference Expression
            //Tracking Perference Expression has been updated to require Tk: N rather than Tk: 1
            Common::sendHeader('Tk: N');
        }
    }