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All of these cookies can be controlled with the cookieProps setting and given a SameSite=None attribute, but that will break all non-current macOS and iOS Safari browsers. We have no plans to provide any kind of mechanism to conditionally apply the rule.
Finally, note that a typical source of problems for most applications is going to be load balancer behavior. If you're using cookies for node affinity, you're going to have problems with SameSite unless you do something about it.
Session Cookies
There is at least one, and possibly two (if the optional recovery feature is enabled), cookies created to track each session. These cookies are created only after the form POST is delivered from the IdP, and so are technically not cross-site in the general sense. In most cases, they do not need to be marked SameSite, and in fact to do so is to defeat the entire rationale behind the change Google is making.
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