Contact form pre-filling form fields with URL parameters not working for logged-in users

#### Steps to reproduce the issue

1. Click here: https://leandroperez.com.ar/en/contact/?id=contact-form-13184&g13184-subject=Prints

#### What I expected

The contact form should show Prints in Subject dropdown.

#### What happened instead

It doesn't select Prints, instead it shows the first option in the dropdown.

Start by reproducing the contact form at the supplied URL while logged in and while logged out. Trace how the g13184-subject URL parameter is handled and compare the selected value in the Subject dropdown. Done means the parameter selects Prints for logged-in users without changing the existing anonymous-user behavior.

Written by the indexing model from the issue text.