I had the same problem. It seems the environment variables used at the function bbp_logout_url inside
bbp-common-functions.php was not working well at http server here or are deprecated. So, I changed the line <$redirect_to = home_url( isset( $_SERVER ) ? $_SERVER : ” );> with this one <$redirect_to = $_SERVER.$_SERVER;>. I do not know if this fixed the problem definitly , because i am testing yet, but the redirect error stoped to occur.
