Incorrect message: Unable to send the cookie. Maximum number of cookies would be exceeded

[ihor-sviziev]

Previously this issue was reported in #7931 and #16568, but no one was able to reproduce it.

Preconditions

1. Magento 2.2.5 installed via composer

Steps to reproduce

1. Open desktop browser Firefox
2. Navigate to about:config
3. Find "dom.storage.enabled" option and change to "false"
4. Navigate to Magento 2.2.5 (frontend), open developer tools >> Storage >> Cookies and look at list (there are 33 cookies)
   
5. Duplicate tab (open the same page in another page) - you will have 43 cookies.
   
6. Try to duplicate tab again - you will have 52 cookies.
   

Expected result

1. Cookies list should not grow such fast

Actual result

1. We can take more then 50 cookies that leads to exception that described in Unable to send the cookie. Maximum number of cookies would be exceeded #7931 and local/session storage is mismanaged, particularly when it doesn't exist #16568

Tech note

I investigated issue described in #16568 and found that we have 2 different polyfill implementaions for localStorage and sessionStorage:

1. Added to page html (https://github.com/magento/magento2/blob/2.2-develop/app/code/Magento/Theme/view/frontend/templates/js/polyfill.phtml)
2. As part of jquery.storageapi library - https://github.com/magento/magento2/blob/2.2-develop/lib/web/jquery/jquery.storageapi.min.js

These implementation are fully different. 1st one works good, but 2nd one adds strange behavior - adds separate cookie with ls_ prefix in name for each item that should be stored in localstorage and ss_<some_id>_ for session storage. As result - when customer goes through website - it will add new and new cookies (because of this strange ss_<some_id>_ prefix).

Sometimess, we're having 2nd implementation used instead of 1st one.

[magento-engcom-team]

Hi @ihor-sviziev. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento-engcom-team give me {$VERSION} instance

where {$VERSION} is version tags (starting from 2.2.0+) or develop branches (2.2-develop +).
For more details, please, review the Magento Contributor Assistant documentation.

@ihor-sviziev do you confirm that you was able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

@ihor-sviziev, thank you for your report.
We've acknowledged the issue and added to our backlog.