How to make "remember me" features work?

[othermaciej]

Many websites have an option to remember certain things, typically the username, even after the user logs out (whether explicitly or via timeout). If setLoggedOut immediately clears all first party state (does it? this isn't really explained in the explainer yet), then these features likely can't work. Do we need a provision for them?

[johnwilander]

This has now been ported to the W3C repo. Please continue the discussion there.