I have a read only select defined by the formbuilder:

```
    ->add('sampledBy', EntityType::class, array(
        'class' => 'AppBundle:FOSUser',
        'query_builder' => function (EntityRepository $er) {
            return $er->createQueryBuilder('u')
                ->orderBy('u.cn', 'ASC');
        },
        'choice_label' => 'cn',
        'disabled' => true
    ))

```

Which I use JQuery to update from another field in my form. Following [this](https://stackoverflow.com/questions/368813/html-form-readonly-select-tag-input) answer, I've set the select up so that it can't be changed by the user:

\*Set it to disabled on create.

\*Before submit set it to `disabled = false`:

```
 $(form).on('submit', function() {
     $("select[id$='sampledBy']").prop('disabled', false);
 });

```

Now, on submit I see the select field change to `disabled = false` (the colour changes back to white and it's clickable while the form submits. However, the data isn't saved. 

Has anyone seen similar behavior? The JQuery appears to work correctly, so I'm wondering if it's a Symfony specific issue.