Solution: https://www.prestashop.com/forums/topic/364875-how-to-delete-cookies-customers/?tab=comments#comment-2348354
Overriding the method __construct (classes/Cookie.php) changing the commented lines
override/classes/Cookie.php
class Cookie extends CookieCore
{
public function __construct($name, $path = '', $expire = null, $shared_urls = null, $standalone = false, $secure = false)
{
$this->_content = array();
$this->_standalone = $standalone;
$this->_expire = is_null($expire) ? time() + 1728000 : (int)$expire;
$this->_path = trim(($this->_standalone ? '' : Context::getContext()->shop->physical_uri).$path, '/\\').'/';
if ($this->_path{0} != '/') {
$this->_path = '/'.$this->_path;
}
$this->_path = rawurlencode($this->_path);
$this->_path = str_replace('%2F', '/', $this->_path);
$this->_path = str_replace('%7E', '~', $this->_path);
$this->_domain = $this->getDomain($shared_urls);
//remove www from url > example: .domain.com
$this->_domain =str_replace('www','', $this->_domain);
//Change cookie name "PrestaShop" > "MyCookieName" This will make all your customers cookies obsolete.
$this->_name = 'MyCookieName-'.md5(($this->_standalone ? '' : _PS_VERSION_).$name.$this->_domain);
$this->_allow_writing = true;
$this->_salt = $this->_standalone ? str_pad('', 8, md5('ps'.__FILE__)) : _COOKIE_IV_;
if ($this->_standalone) {
$this->_cipherTool = new Blowfish(str_pad('', 56, md5('ps'.__FILE__)), str_pad('', 56, md5('iv'.__FILE__)));
} elseif (!Configuration::get('PS_CIPHER_ALGORITHM') || !defined('_RIJNDAEL_KEY_')) {
$this->_cipherTool = new Blowfish(_COOKIE_KEY_, _COOKIE_IV_);
} else {
$this->_cipherTool = new Rijndael(_RIJNDAEL_KEY_, _RIJNDAEL_IV_);
}
$this->_secure = (bool)$secure;
$this->update();
}
}