Until a different unpowered human-readable medium is proven over a longer period of more careless storage conditions, looks like a third edition if appropriate.
If it hasn't been printed it hasn't really been published as thoroughly as it could be, and if it hasn't been bound then it's not yet a real book. Up until recent decades the survival of unique knowledge was largely dependent on the number of copies printed and distributed, so popularity has had undue importance.
But don't let earlier editions become lost or woe on you.
The second edition.
And how could books be improved?
Until a different unpowered human-readable medium is proven over a longer period of more careless storage conditions, looks like a third edition if appropriate.
If it hasn't been printed it hasn't really been published as thoroughly as it could be, and if it hasn't been bound then it's not yet a real book. Up until recent decades the survival of unique knowledge was largely dependent on the number of copies printed and distributed, so popularity has had undue importance.
But don't let earlier editions become lost or woe on you.