How to fix «Unable to send the cookie. Maximum number of cookies would be exceeded»

dmitrii_fediuk · November 17, 2015, 4:52am

Looks like Magento 2 uses an obsoleted specification RFC 2109 for cookies limit.
The new specification is RFC 6265, and it allows at least 50 cookies per domain.

So the MAX_NUM_COOKIES limit can be safely increased up to 50.

Locate the line:

github.com

magento/magento2/blob/daf301d625d8652996a6d3c9400e5f9816184bde/lib/internal/Magento/Framework/Stdlib/Cookie/PhpCookieManager.php#L27


* sensitive data so that extra protection can be added to the contents of the cookie as well as how the browser
* stores the cookie.
*/
class PhpCookieManager implements CookieManagerInterface
{
   /**#@+
    * Constants for Cookie manager.
    * RFC 2109 - Page 15
    * http://www.ietf.org/rfc/rfc2109.txt
    */
   const MAX_NUM_COOKIES = 20;
   const MAX_COOKIE_SIZE = 4096;
   const EXPIRE_NOW_TIME = 1;
   const EXPIRE_AT_END_OF_SESSION_TIME = 0;
   /**#@-*/


   /**#@+
    * Constant for metadata array key
    */
   const KEY_EXPIRE_TIME = 'expiry';
   /**#@-*/

Replace it with the new one:

const MAX_NUM_COOKIES = 50;

See https://github.com/magento/magento2/issues/1500#issuecomment-156421883