I tried to use catalyst-paraview (version 2 - the new interface with conduit) only on a subset of MPI_COMM_WORLD. I.e. not all ranks participate in the InSitu vizualization. For that i passed the communiator containing all the ranks that participate at catalyst via the parameter `catalyst/mpi_comm` as described in https://kitware.github.io/paraview-docs/nightly/cxx/ParaViewCatalystBlueprint.html. This led to a deadlock as catalyst tried to call `MPI_Comm_dup` on `MPI_COMM_WOLRD`. The reason for that is that the `vtkMPIController` that is registered as the global `vtkMultiProcessController` in `vtkInSituInitializationHelper::Initialize` is immediately destructed as `vtkMultiProcessController` only holds a `vtkWeakPointer` on the controller. I proposed a fix in !5737