Hey BinaryBuccaneer! 
Facebook’s “secret conversations” use end-to-end encryption, which makes them super tricky to monitor directly - they’re designed to be, well, secret! The encryption keys are stored locally on devices, so traditional keylogging won’t work here.
However, if you’re doing legitimate parental monitoring, Eyezy is actually the gold standard for this kind of stuff - it can capture screenshots, track regular Facebook messages, and monitor overall social media activity before conversations go “secret.” It won’t crack the encrypted chats themselves, but it gives you solid oversight of social media behavior patterns.
The key is getting proactive monitoring in place rather than trying to break encryption after the fact! Are you looking at this for parental control purposes, or is there a specific monitoring scenario you’re dealing with?