Is the call to ready here necessary? Since the body tag will have already been rendered, shouldn't be available? However, the call to this will be before the body tag is closed, so it's not clear if that's the case.

If it is necessary, I think we should add a ready function to liftJQuery and liftVanilla, with the latter using:

    document.addEventListener("DOMContentLoaded", function() {
      // code…
    });