Hello.
This code is not for 1.7.6.x. We have already solved.
Example of code for 1.7.6.x, Category Page with new field (choices):
public function hookActionCategoryFormBuilderModifier(array $params) { $formBuilder = $params['form_builder']; $formBuilder->add('ID_MODULE', ChoiceType::class, [ 'label' => $this->getTranslator()->trans('YOUR FIELD NAME', [], 'Modules.MODULE'), 'required' => false, 'choices' => [ ... ], ]); $category_id = $params['id']; $params['data']['ID_MODULE'] = $this->getCategoryBolhaId($category_id); $formBuilder->setData($params['data']); }