I am trying to create a form that would have a hidden field populated automatically by the url I send to people that should fill the form. 

So, assuming my form is located in address

http://myform

I would like to send an address lilke

http.//myform?hiddenfield=1234

As long as I have the hiddenfield visible, everything works smoothly. but once I try to hide the field, the value is no more stored by the form. I can see that the field exists in the page source html, and has the proper value set, but it does not end up into my integrated google sheet, but stays stubbornly blank. 

am I doing something wrong, or should this work?

Thanks, 

Teemu