In the activty diagram (beta) there is some unexpected behavior when combining forks and swimlanes
I would expect the fork to be in the B-swimlane, and not the A-swimlane.
@startuml
|A|
|B|
|C|
|B|
:Something;
fork
|A|
:monkey;
forkagain
|C|
:Ape;
endfork
@enduml