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Codidact Meta is the meta-discussion site for the Codidact community network and the Codidact software. Whether you have bug reports or feature requests, support questions or rule discussions that touch the whole network – this is the site for you.
Signing in should sign you in on all sites
It looks to me like the session cookie that holds one's user session credentials is currently bound to the specific site.
The result of this is that you need to sign in separately to, say, Scientific Speculation and Codidact Meta.
If that is correct, then if the cookie was set to apply to all subdomains of
codidact.com instead of simply the one the user signs in to, switching between sites wouldn't require signing in separately on each.
Either way, I'd like to not need to sign in separately on each site under codidact.com.
Similarly, signing out should sign you out of all sites, not just the one where you click "sign out".