I'm trying to show with one detail two separate areas that the Actor in the detail view is showing.
Why don't you create two details rectangular and place them next to each other?
This is how I do it: I create a blank detail view, set the size to minimum, choose the tail (tooltip), drag the little blank detail view outside the paper, drag the tail from this blank detail view to the detail view that needs 2 tails – see screenshot below.
Hope this is what you are looking for.
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