Incompatible with PHP 5.4.x

Yeah, PHP intentionally is no longer allowing that. https://www.php.net/manual/en/migration54.incompatible.php Same goes for $_GET, $_POST, $_REQUEST, etc. Here is a fix for this plugin.

class.gaparse.php:

function __construct($_COOKIE) {
       $this->utmz = $_COOKIE["__utmz"];
       $this->utma = $_COOKIE["__utma"];
       $this->ParseCookies();
  }

change to:

function __construct($cookie) {
       $this->utmz = $cookie["__utmz"];
       $this->utma = $cookie["__utma"];
       $this->ParseCookies();
  }

can confirm this fixes for me