Why browsers do not accept cookies from the site?

Question

Google Chrome

There is a shop site with storage of a basket in cookies. Everything worked fine, but recently I noticed that in Firefox, when adding to the cart, products began to be added selectively.
I thought the error crept into the code, but after long dances with a tambourine it turned out that the code was in order.
It turns out that Chrome does not want to add a single product to the cart at all.
Somehow I came across an article that sites using cookies must necessarily warn the user about this and all that - maybe this policy has already been implemented in the browser code?
Or what could be the catch?

Answer 1

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