  Kastner (arXiv:1709.09367) and Kastner and Cramer (arXiv:1711.04501) argue
that the Relativistic Transactional Interpretation (RTI) of quantum mechanics
provides a clear definition of absorbers and a solution to the measurement
problem. I briefly examine how RTI stands with respect to unitarity in quantum
mechanics. I then argue that a specific proposal to locate the origin of
nonunitarity is flawed, at least in its present form.
