Creating form fields "for office use only"

If you want to be able to add notes to form submissions, you can add a "for office use only" field. You don't have to find ways to hide it from the user, or make the default value something like "do not type in this field" - instead, there's one simple setting that you should set.

In the "advanced" tab of the field, in the "administration" section, simply check the box "private" and save the field. Now only people who have access to the form results can see the field.

Now, your office use field is hidden from regular people filling in the form, but you can edit the submissions to add whatever private information you want!