I found a way to open the same world multiple times.
There is a world called "8-bit.MCL" now.
What you do is copy/paste, rename. It's simple, really. You would get "8-bit.MCL", "8-bit(b).MCL", "8-bit(c).MCL", "8-bit(d).MCL", "8-bit(e).MCL", "8-bit(f).MCL", "8-bit(g).MCL", "8-bit(h).MCL", "8-bit(i).MCL", "8-bit(j).MCL", and "8-bit(k).MCL".
And now you open all at once.
Use different characters in the same world.^_^
There is a world called "8-bit.MCL" now.
What you do is copy/paste, rename. It's simple, really. You would get "8-bit.MCL", "8-bit(b).MCL", "8-bit(c).MCL", "8-bit(d).MCL", "8-bit(e).MCL", "8-bit(f).MCL", "8-bit(g).MCL", "8-bit(h).MCL", "8-bit(i).MCL", "8-bit(j).MCL", and "8-bit(k).MCL".
And now you open all at once.
Use different characters in the same world.^_^