On another Lemmy instance, I saw that I was not logged in but could subscribe by putting “!emulation@lemmy.ml” into the search field. However, when I put it into the search field of this Lemmy instance, it gives me a comment containing that string, but does not allow me to subscribe.
What is the correct way to do it?
What you are doing is right, but it takes some time for your instance to set up the connection to the new community. Give it a few minutes, then search for the community by its plain name (e.g. emulation) under all.