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How do I resolve this error, 'Trying to get property of non-object in /.../libraries/joomla/session/handler/joomla.php on line 74'? Here's line 74 or the joomla.php file, $cookie = $this->input->cookie;. This started after updating the site to Joomla 3.7 and PHP 7.0, but also shows up with PHP 5.6. The site is running CiviCRM 4.7.18.