From the FreeBSD architecture handbook (https://www.freebsd.org/doc/en/books/arch-handbook/jail-restrictions.html) as it relates to `allow.sysvipc`, "By default, this sysctl is set to 0. If it were set to 1, it would defeat the whole purpose of having a jail; privileged users from the jail would be able to affect processes outside the jailed environment." This is undesirable behavior.
Per `man jail`, regarding `allow.sysvipc`, "A process within the jail has access to System V primitives. This is deprecated in favor of the per-module parameters."
Since FreeBSD 11, the new way to deal with this (the per-module parameters) is with: `sysvshm`, for shared memory, `sysvsem`, for semaphores, and `sysvmsg`, for message queues. These can be set selectively to either `disable`; `inherit`, for the previous behavior (problematic due to UID collision, apparently); and `new`, for new behavior that avoids the UID collision problem.
Monero only uses semaphores, therefore we should recommend that jails be run with `sysvsem="new"` in the jail's jail.conf. Tested on FreeBSD 12.1.
Also, Monero is now able to be downloaded as a package or built from ports as `monero-cli` with a versioned suffix. It's got `Monero 'Carbon Chamaeleon' (v0.15.0.1-release)` as of right now, and it's been there 2-3 months, meaning it's currently and timely.
10 block lock time is for incoming outputs and not only incoming transactions (outgoing transaction has an incoming change output that is also locked for 10 blocks)