A message informs you that the new selected referential will override the
previously loaded referential (if any) and asks you to click:
- OK to confirm your selection.
- Cancel to keep the current referential (and save
changes that have not been already saved in the experience, for
instance).
Loading an experience has the same effect because an experience is always
associated to a referential. This means that once you start an experience,
you cannot change its referential.