Partitioned Cookies

The Partitioned cookie attribute isolates a third-party cookie by the top-level site that embedded it.

Use Partitioned only for a cross-site embedded service that needs state in separate site contexts. Partitioned cookies must also use Secure.

httpcookiesprivacythird-party

Reference (http)

Set-Cookie: widget_session=abc; Secure; HttpOnly; SameSite=None; Partitioned

Use Partitioned only for a cross-site embedded service that needs state in separate site contexts. Partitioned cookies must also use Secure.

Common mistakes

Assuming Partitioned makes a cookie first-party or removes the need to consider third-party cookie blocking.

Sources