code: public function updateItemEditForm($form)
      {
          if ($this->owner->record->stat('better_buttons_enabled') !== true) {
              return false;
          }
          Requirements::css(BETTER_BUTTONS_DIR.'/css/gridfield_betterbuttons.css');
          Requirements::javascript(BETTER_BUTTONS_DIR.'/javascript/gridfield_betterbuttons.js');
  
  
          $actions = $this->owner->record->getBetterButtonsActions();
          $form->setActions($this->filterFieldList($form, $actions));
  
          if ($form->Fields()->hasTabSet()) {
              $form->Fields()->findOrMakeTab('Root')->setTemplate(TabSet::class);
              $form->addExtraClass('cms-tabset');
          }
  
          $utils = $this->owner->record->getBetterButtonsUtils();
          $form->Utils = $this->filterFieldList($form, $utils);
          $form->setTemplate([
              'type' => 'Includes',
              'BetterButtons_EditForm',
          ]);
          $form->addExtraClass('better-buttons-form');
      }
docs: Updates the detail form to include new form actions and buttons
  
  @param Form The ItemEditForm object