This is a summary of our current understanding of the impact of the Chrome SameSite change that has been well-publicized, and has been rolling out in recent Chrome (and now Edge, and other Chromium software) versions in a haphazard fashion. As of January 2022, Firefox has apparently rolled out the same change.
If you want the gory details, we have a very technical testing summary page at IdP SameSite Testing. This is intended as a more digestible, actionable summary for deployers.
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