When you create nested component, portout is in wrong location.
@startumlcomponent C { portout p1 portout p2 portout p3 component c1 component c2 component c3}[o]p1 --> op2 --> op3 --> oc1 --> p1c1 --> c2c2 --> c3@enduml
Hi M., and all,
[Just for traceability,] See similar defects/requests here:
Regards.
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