I am trying to remove the value(_blank) of attribute[‘target’] variable in form_state when the value I get empty i.e. when the checkbox is unselected.

public function submitForm(array &$  form, FormStateInterface $  form_state) { $  response = new AjaxResponse();  if ($  form_state->getErrors()) {   unset($  form['#prefix'], $  form['#suffix']);   $  form['status_messages'] = [     '#type' => 'status_messages',     '#weight' => -10,   ];    $  response->addCommand(new HtmlCommand('#linkit-editor-dialog-form', $  form));  } else {   // This was I tried         if(empty($  form_state->get('attributes')->target)){       $  form_state->setValue($  form_state['attributes']['target'], "_TEST");     #$  form_state->setValue('attributes', "_TEST");     #$  form_state->setValueForElement('target', "_TEST");    }   // End   $  response->addCommand(new EditorDialogSave($  form_state->getValues()));   $  response->addCommand(new CloseModalDialogCommand()); }  return $  response; 

}

After execution the code I got wrong array

Any help? Thanks in advance.