I'm currently trying out the free version and have a form with a hidden input. I'd like to populate that via the query string on the page where the form is embedded (using the JS snipped).

I have appended the initialization script with ?SingleLine=12345 and it all looks good in my html source when looking through chrome devtools.

The problem is, that data is not saved when the form is submitted. If I set the field to be visible then it saves properly, but I want it to be invisible to the end user.

My question is, how to have an invisible input that is populated from the query string and have it save to the database.