pfSense

I confirm that the fix is working. Name of the user is now recorded in captiveportal status and logs on last snapshot.

Also, if you want to forbid empty names, i suggest to create a custom login page that block empty names using javascript.
If you really want to forbid empty names, you could include a patch at the begining of /usr/local/captiveportal/index.php

if (empty ($_POST['auth_user']) || $_POST['auth_user']==='unauthenticated') {

    log_error("Submission to captiveportal with empty user name");

    portal_reply_page(null, "error", gettext("Empty names forbidden"));

    ob_flush();

    return; 
}

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