I add
public function validateForm(array &$form, FormStateInterface $form_state) {
}
to MymoduleMyentityForm.php which starts with
namespace Drupal\association\Form;
use Drupal\Core\Entity\ContentEntityForm;
use Drupal\Core\Form\FormStateInterface;
Then I run the form and when I submit it, I get this error: Uncaught PHP Exception Drupal\Core\Entity\EntityStorageException: "Entity validation was skipped." at /Applications/MAMP/htdocs/JdP8/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php line 770
Any idea why? What am I doing wrong?