How to fix ActionDispatch::Cookies::CookieOverflow error on heroku?
Rails cookies are limited to 4KB. Note that the session is stored in the cookie in the default configuration too. See: http://guides.rubyonrails.org/security.html#session-storage
The only thing you can do about that: Do not store big objects in the cookie. Store them in the database and then only store the object's id in the cookie.
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