transform(value, arg) {
   if (value == null) {
     return null;
   }
   let section = arg.pop();
   let addEnd = (value[value.length - 1].pme_id !== section.pme_id);
   let endPos = value.length + 1;
   let ret =
       value
           .filter(
               elt => (section.pme_id !== elt.pme_id && section.pme_order !== elt.pme_order - 1))
           .map(elt => {
             elt.pme_name = this.i18n.t('portal.move.before_something', {what: elt.pme_name});
             return elt;
           });
   if (addEnd) {
     ret.push({pme_name: this.i18n.t('portal.move.at_the_end'), pme_order: endPos});
   }
   return ret;
 }

 .map(elt => {
   elt.pme_name = this.i18n.t('portal.move.before_something', {what: elt.pme_name});
   return elt;
 });

 .catch(error => { this.errormsg = this.i18n.t('auth.autherror'); });

 .catch(err => {
   this.alerts.danger(this.i18n.t('portal.alerts.error_loading_mainview_elements'));
 });