Log compression isn't working as expected

Hi Guys, I found this new great feature of mariadb (log compression), but unfortunately i cannot make it working. Basically on the servers we're writing terabytes of logs on SSD disks so that would be great if I can get it enabled.

log_bin_compress_min_len=10
log_bin_compress=1

log_bin_compress_min_len=10
log_bin_compress='ON'

log_bin_compress_min_len=128
log_bin_compress='ON'

Nothing works as expected. I tried enabling by SET GLOBAL and also using config file
https://mariadb.com/kb/en/library/compressing-events-to-reduce-size-of-the-binary-log/

Still there's plaintext in the log and it doesn't seem that anything is getting compressed... i'm doing something wrong or this feature is no longer supported / broken in 10.2.9?

Log file dump:
https://www.screencast.com/t/08Ig7s023Jzg

Thanks,
Slawomir.