Just because the idea of bubble universes is so cool:
Besides the fact that we can’t ever contact them, keep in mind also that the laws of physics may operate differently in each one, making life or even stars impossible in many or most.
And it certainly doesn’t mean “parallel Earths”, where another copy of you exists. Whew, that’s hubris, isn’t it?
Sorry, Rose, no “Pete’s World” for you. 😀