Is "immediate" timing of Input constraints implemented yet?

Is the “Immediate” timing of an Input constraint implemented yet? If yes, what are the requirements to have this work?

Release notes mentioning being supported later on:

Documentation explaining the option, but not mentioning it not being supported yet.
https://docs.thinkwisesoftware.com/docs/sf/domains#add-dynamic-domain-input-constraints

At least on 2023.3 not seem to be able to make it work, but Indicium and the Universal GUI are up-to-date. Maybe 2024.1 is required, but I think the functionality is GUI located.