Here is the official answer from WorkFront customer care - I didn't know this. I'm happy I asked.
Hi Eric, Thanks for your message. Currently for submitting feature requests you need to use our previous Helpdesk:
https://helpdesk.workfront.com/login . Our updated Support Site:
https://support.workfront.com should be used for a) getting help; b) reaching out to the WF Community; and c) logging tickets all from one place. However, we are also planning to include the option for submitting Feature Requests in the current Support Site to make our Customers' experience easier and handy. I will make sure to keep you posted about the upcoming changes. Kindly, Anna