[dev] How to pre-populate recipient via link in AgentTicketForward

Hi all, we need to regularly send documents to our document management system. To do so I want to add an article action that does pre-populate AgentTicketForward with the email address of the DMS. I tried to achieve the goal building a link like this: /otrs/index.pl?Action=AgentTicketForward;TicketID=4;ArticleID=4;ToCustomer=customer@example.com;Subject=Forward%20To%20DMS;Body=Forwarded%20Documents Subject and Body are prepopulated correctly. But the ToCustomer field won't be filled. Anyone knows if and how I can prefill the ToCustomer field? Thanks, Daniel