If a pre-fork output is spent on both Monero and attack chain,
any post-fork output can be deduced to be a fake output, thereby
decreasing the effective ring size.
The segregate-per-fork-outputs option, on by default, allows
selecting only pre-fork outputs in this case, so that the same
ring can be used when spending it on the other side, which does
not decrease the effective ring size.
This is intended to be SET when intending to spend Monero on the
attack fork, and to be UNSET if not intending to spend Monero
on the attack fork (since it leaks the fact that the output being
spent is pre-fork).
If the user is not certain yet whether they will spend pre-fork
outputs on a key reusing fork, the key-reuse-mitigation2 option
should be SET instead.
If you use this option and intend to spend Monero on both forks,
then spend real Monero first.
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