> 3) ?????? I can't think of anything else, can you ?
I think the page could be basically blank, with "loading" or some
customisable message. If that causes a one-off flicker, I don't think
it matters, because activity is what people are wanting.
And yes, it would need to be erased, but presumably it could be easily
identified in the DOM and thus deleted once things got going properly.
(I'd also not worry too much about errors like a file missing. If
that's broken, too bad!)