Consider this diagram:
@startuml
' hide stereotype
skinparam ParticipantBorderColor<<type>> #Black
skinparam SequenceLifeLineBorderColor<<type>> #Black
participant Bob <<type>>
@enduml
Running as is, the boxes around "<<type>> Bob" will be black, as well as the dashed lifeline.
If I'd rather remove "<<type>>" from the boxes, then I must uncomment "hide stereotype".
When I do so, the lifeline goes back to the default red color, but the box border color remains black. Shouldn't either both properties be applied, or both be ignored? The current behavior appears to be a bug. Are there any workarounds, or could this be fixed in a future version?