pgadmin4/web/pgadmin/preferences/static/scss/_preferences.scss

.preferences_tree{
  padding: 0px;
  padding-top: 2px;
  height: 100%;
  overflow: auto;
  border-right: $panel-border;
}

.btn-checkbox {
  padding: $btn-checkbox-padding;

  & input[type="checkbox"]{
    margin-top: 0px !important;
  }
}