I want to get a User via JSOM.
The User is not the current user. The object I want to get should be SP.User (not String or anything) I want to get the User by asking for his login ("domain\username") and get back the SP.User object.
I found some solutions using the PeopleManager. But I'm not sure if this is the correct way. Because if I get the PreferredName, isn't this just a string?