Workflow: How to access message @ sink mail

I m able to create a sink route for email. The route gets triggered if i send a mail.
(I can write a random text to my module every time the mail gets received)

But i m not able to find out how to access the initial scope “message”, so that i can do something with it. Is there something missing here (events.gen.go, Line 1897)? Not sure, haven’t debugged it, only searched in the code for some hints and stumbled about it. What do i miss? Hot do i access message body and message header?

// Encode internal data to be passed as event params & arguments to workflow
func (res mailBase) EncodeVars() (out *expr.Vars, err error) {
out = &expr.Vars{}
var v expr.TypedValue

// Could not found expression-type counterpart for *types.MailMessage

// Could not found expression-type counterpart for auth.Identifiable

_ = v

It seems to me that we did miss something there…
I’ll open up a ticket so one of us can look into it and resolve it if needed.