When looking at registerModule in the vuex documentation it becomes clear, that one can register a whole module after a store has been created.
Looking further, it seems possible to add a new Set of actions, getters and mutations and keep the state with the option preserveState set to true.

However, the documentation does not cover the option to just add another action after a module has been registered and keep all the rest.

Has anyone run into the same problem at some point?