Form with individual subject

Hi all,

I have a question about using the standard form option. I have a contact form on a website. If someone sends the form we receive an email with the subject “Contact via website”. As we receive quite a lot of contacts, we would like to implement a field where senders can put their individual subject so what their contact is about. This field shall be shown as subject in the emails we receive. Is there a way to do so or do you have other ideas?

Thanks in advance,
Sebastian