unm:chrono:userlib and from-unix-ms:chrono:userlib are sometimes not invertible #4598
Description
(unm:chrono:userlib (from-unix-ms:chrono:userlib 1.615.573.389.789))
1.615.573.389.788
(unm:chrono:userlib (from-unix-ms:chrono:userlib 1.615.573.389.000))
1.615.573.389.000
Seems to have been introduced here, but his logic seems correct at a glance. Very confused.