How to make “login after registration” work.

You need to paste the code below, after the wp_signon function near line 525 in clean-login.php for users to be fully logged in after registering (when option “Automatically Login after registration?” is active). If it is not, features like forums, and other plugins won’t work correctly after the user registers with your plugin. This is also mentioned in official WordPress documentation here: wp_signon() under the “Description” section of the last paragraph beginning with “Note:”.

Please update your code so I don’t have to permanently disable updates for your plugin, and let me know when this accomplished. Thanks.

wp_clear_auth_cookie();
wp_set_current_user( $user->ID );
wp_set_auth_cookie( $user->ID );