Note that this happens even if you're going to lose money on your investment.
I made a video about some possible outcomes: https://www.youtube.com/watch?v=LYFqQ6yk9vs
No idea about shorts. I would assume that the short seller would simply have to pay the original owner the end purchase price.
By default it would be something like - if the board approved it goes to a shareholder vote, and if 75% or 90% of the shareholders approve the rest are dragged.
I doubt the board can force all shareholders to sell, that would be an insane power position for shareholders
search "Inst Own" https://finviz.com/quote.ashx?t=TWTR
That's actually crazy to think about... so besides Elon, only 11.6% of shares are privately held? Meaning Elon holds about half of all privately held shares? Unless somehow he is in the 78.4% but I don't think so.
Edit: I also wonder how leveraged positions, especially shorts, get resolved.