Deprecate the storefront CSRF implementation

INFO

This document represents an architecture decision record (ADR) and has been mirrored from the ADR section in our Shopware 6 repository. You can find the original version here

Context

• With browsers evolving and dropping support for older browser in 6.5 we have wide support for SameSite cookies.
• The current CSRF implementation adds a lot of complexity to all forms and ajax calls in the Storefront.
• The CSRF protection does not add a great improvement in security due to the SameSite strategy.

Decision

• We remove the CSRF protection in favor of SameSite cookies which are used and prevent CSRF attacks already.

Consequences

• All CSRF implementations in the Storefront will be removed.