YiiBooster gridview not registering change events on filter

There’s an issue driving me mad. I have a view with a simple GridView, implemented using YiiBooster but behaves the same using the core CGridView.
The filter doesn’t trigger search. Inspecting the HTML, there are no change or keydown events, like in other gridviews.

The model implements rules for the search scenario.

I really cannot spot where’s the problem. I hope someone can give a hint. Thanks.

The model’s search():

    public function rules()
        // load validation rules folder

        // scenarios for the password_confirm
        // registration is added depeding on the configuration parameter
        $passwordConfirmScenarios = array('recovery', 'changePassword');
        if (UserGroupsConfiguration::findRule('registration_password_confirm') === true)
            $passwordConfirmScenarios[] = 'registration';

        // rules
        $rules = array(
            array('group_id', 'length', 'max' => 20),
            array('username, password, home', 'length', 'max' => 120),
            array('email', 'email', 'checkMX' => true),
            array('rememberMe', 'safe'),
            // rules for activation
            array('username, activation_code', 'required', 'on' => 'activate'),
            array('activation_code', 'checkCode', 'on' => 'activate'),
            // rules for passRequest
            array('username, email', 'required', 'on' => 'passRequest'),
            array('email', 'checkMail', 'on' => 'passRequest'),
            array('answer', 'securityQuestion', 'on' => 'passRequest'),
            // rules for mailRequest
            array('mail', 'requestableMail', 'on' => 'mailRequest'),
            // rules for changePassword
            array('old_password', 'required', 'on' => 'changePassword'),
            array('old_password', 'oldPassMatch', 'on' => 'changePassword'),
            // rules for admin
            array('group', 'levelCheck', 'on' => 'admin'),
            // rules for multiple scenarios
            array('username, password', 'required', 'on' => array('login', 'registration')),
            array('email, old_password, password, password_confirm', 'accountOwnership', 'on' => array('changeMisc', 'changePassword')),
            array('email', 'required', 'on' => array('registration', 'admin', 'mailRequest', 'changeMisc', 'invitation')),
            array('username, email', 'unique', 'on' => array('registration', 'admin', 'recovery', 'changeMisc', 'invitation')),
                'username', 'match', 'pattern' => '/^[A-Za-z0-9]{4,}$/', 'on' => array('registration', 'admin', 'recovery'),
                'message' => Yii::t('userGroupsModule.general', 'username must be at least 4 characters and can only be alphanumeric')
            array('password', 'required', 'on' => array('recovery', 'changePassword')),
            array('password', 'passwordStrength', 'on' => array('registration', 'admin', 'recovery', 'changePassword')),
            array('password_confirm', 'required', 'on' => $passwordConfirmScenarios),
                'password_confirm', 'compare', 'compareAttribute' => 'password', 'on' => $passwordConfirmScenarios,
                'message' => Yii::t('userGroupsModule.general', 'La password di conferma non coincide')
            // The following rule is used by search().
            // Please remove those attributes that should not be searched.
            array('id, group_name, group_id, username, home, status', 'safe', 'on' => 'search'),

        if (UserGroupsConfiguration::findRule('simple_password_reset') === false)
            array_push($rules, array('question, answer', 'required', 'on' => array('recovery', 'registration', 'changePassword')));

        if (UserGroupsConfiguration::findRule('registration_captcha') === true) {
            array_push($rules, array('captcha', 'required', 'on' => 'registration'));
            array_push($rules, array('captcha', 'captcha', 'on' => 'registration'));

        return $rules;

The controller:

    public function actionUtenti()
        $this->layout = 'column2';
        $model = new UserGroupsUser('search');
        if (isset($_GET['UserGroupsUser']))
            $model->attributes = $_GET['UserGroupsUser'];

        $this->render('utenti', array(
            'model' => $model,

The view:


/** @var UserGroupsUser $model */
/** @var SiteController $this */
$this->breadcrumbs = array(
    Yii::t('Backend', 'Elenco'),


<h1>Gestione utenti</h1>


$this->widget('bootstrap.widgets.TbGridView', array(
    'id' => 'aaaa-grid',
    'dataProvider' => $model->search(),
    'filter' => $model,
    'columns' => array(
    'pager' => array(
        'class' => 'bootstrap.widgets.TbPager',
        'displayFirstAndLast' => true,