Is it possible to have a multi selection dropdown field in ActiveCampaign?

We would like to give our customers the option to subscribe to our newsletter, however, because we have 5 different products we have 5 newsletters. We would like to give our customers the option to subscribe to 1 or more lists, but also prefer the design of a dropdown field over 5 checkboxes. Is it possible to move the checkboxes into a dropdown list?

I have also tried the multi selection field, however this requires the customer to select multiples using command or control.

I have found a way on here where it is possible, however this way is via building your form from scratch in html. Is it possible to do something like this in the form builder of activecampaign? How to create checkbox inside dropdown?