Customize widget's ID attribute in Twig
Did you try: {{ form_widget(form.title, { 'id': 'my_custom_id' }) }}?
If this still doesn't work, you could also rely on form customization to handle it. But this could be overkill and may not be the best idea. Check the documentation on form theming for more info.
As I said, maybe there is better way but this is only what I can propose you for now.
Hope this helps.
{{ form_widget(form.title, { 'attr': {'id': 'my_id'} }) }}http://symfony.com/doc/current/book/forms.html
I have used it and it works.
I don't know if it can help for googlers but you also can specify the prefix of the attribut in the formType
public function getName(){ return 'vendor_testbundle_sickness';}your attribute will have the folowing id :
vendor_testbundle_sickness_SOMETHING