Sessions: fixed logout() destroying normal session (instead of elevated) if $level = USER_LEVEL_CHPREF. Possible very minor security concern: elevated sessions were not fully destroyed, so if a normal session is opened from the same IP, the elevated one may be reusable for 15 minutes.

form.searchform, td#cell-sbleft {
  background-color: #2b2b2b;
  background-image: none;
}