After that, data are sent to dologin.php to auto authenticate, now I'm retrieving the customparam value using $_GET[customparam]. but when I do, it's blank. So I assume that after the auto authentication parameters were removed? I also tried creating hooks and setting sessions, but after dologin.php, all data disappears.
What I'm trying to do is to be able to retrieve the parameter I add in the URL after dologin.php.