Does this work subdomain to subdomain? For instance, learn.example.com (WordPress) and talk.example.com (Flarum). I've tried this on two different sites I'm setting up, and it does the same thing on both: flarum_remember does get set, but it also expires at the exact second it was set at. The user is not copied over to the Flarum database.
By two different sites I mean the example above and another site that was www.example.com and forum.example.com. This one was not WordPress but a different PHP software (SilverStripe). Both acted in the same manner though.
API key is in the Flarum database and set correctly in the config.php file, along with everything else that needs setup like the private key and URL + base domain name.
Thanks to whoever has an idea on how to fix this set up.