Same here, this has been going on for a couple of weeks. Running Linux Mint 18.3 (based on Ubuntu). Doesn't seem to be related to 2.3.12. I downgraded to 2.3.7 and I still get the error. Sounds like a system update borked a library beersmith depends on.
It would be nice to have a time frame in which this bug might be fixed. Bump?