When a concurrent execution arrives a (joining) parallel gateway and the number of joining executions are reached then the local variables of the last joining execution are copied to the parent execution.
Side effect: two history entries are created for the local variable.
AT:
- no local variables are copied to the parent execution
We could also open another ticket for the case that tree compaction happens.
There, we do want to copy the variables but instead of two historic variable instances, we probably want to update the existing one.