Avoid prefixing global $check_referrer value with protocol prefix - use local variable instead

functions/auth.php

@@ -55,12 +55,12 @@ function sqauth_is_logged_in() {
     if ($check_referrer == '###DOMAIN###') $check_referrer = $domain;
     if (!empty($check_referrer)) {
         $ssl_check_referrer = 'https://' . $check_referrer;
-        $check_referrer = 'http://' . $check_referrer;
+        $plain_check_referrer = 'http://' . $check_referrer;
     }
     if (sqsession_is_registered('user_is_logged_in')
      && (!$check_referrer || empty($referrer)
       || ($check_referrer && !empty($referrer)
-       && (strpos(strtolower($referrer), strtolower($check_referrer)) === 0
+       && (strpos(strtolower($referrer), strtolower($plain_check_referrer)) === 0
         || strpos(strtolower($referrer), strtolower($ssl_check_referrer)) === 0)))) {
         return true;
     }