Widgets are consuming unhandled inputs

Hello, I am creating some kind of factory where I have draggable recipes at the bottom of the screen and a production line in the center. I want to be able to insert recipes into the production line by dropping them onto a DropArea, and not just on the production line widget itself. For this reason, the production line is located under the DropArea.

And now to the problem. I have overwritten OnMouseButton events inside DropArea so that they always return Unhandled, but despite this, it is still not possible to click the button on the line (nor the CloseArea at the very bottom). The visibility of each element is set to Visible (except for the text). Is this behavior correct or did I miss something? Below you can see a simplified preview of the widget.

Did you find the solution? I’m having the same problem…